Emilia Clarke had a headache. It was 2011, just before Valentine’s Day and just after she’d wrapped on the first series of Game of Thrones, playing Daenerys Targaryen, Breaker of Chains, Mother of Dragons. She didn’t yet know, as she crawled into the locker room of her local gym in north London and vomited bile into the toilet, that Game of Thrones would run for seven further seasons, break Emmy-award records for most wins for a scripted television series and for a drama, be named one of the greatest TV shows of all time, and quickly come to define her. But there was much she didn’t know.

She didn’t know that at 24 she had suffered a life-threatening stroke, a subarachnoid haemorrhage (SAH) caused by bleeding into the space surrounding the brain. She didn’t know, as she lay on the floor repeating lines from Game of Thrones in order to test her memory, that a third of SAH patients die immediately, or that those who survive require urgent treatment to avoid a second, often fatal bleed. She didn’t know there was another swollen blood vessel in her brain, which had doubled in size by the time she finished filming season three. She didn’t know that one day, eight years later, over biscuits on her pink sofa, she would be smiling with the dark realisation that her stroke was one of the best things that could have happened to her.

Her pink sofa is in her pink house, which is also green and blue and muted shades of rust, and has a secret bar hidden in a courtyard shed, and an outdoor screening room heated by a wood-burning stove. To walk into her living room, where one corner is painted with a symbol relating to her mum, another to her late dad, and a third with a meaningful dragon, is to enter the cosiest corner of Clarke’s mind. By the stairs, horsehair is visible in the plaster; the walls are stripped back to the bone. She shows me round with a raw sort of glee, a sense that her comfort and safety are bound into the details: the friends’ art on the walls, the “single girl’s” bedroom. She moved in after Game of Thrones; in this and many ways, her life can be cleanly dissected into before and after.

Before, Clarke, now 33, who grew up in Oxfordshire, had appeared in a single episode of the daytime soap Doctors. She was ambitious, optimistic and relentlessly cheerful. After, after Game of Thrones, and the death of her father, which shook her family, as did her life-threatening stroke, she is sitting on her pink sofa and contemplating a decade that changed her.

“And yes, I’m at the point where I definitely think of the brain haemorrhage as a good thing,” she nods. She has extremely expressive eyebrows that appear jointed – for every word Clarke says, and she says many, they add 15 more. “Because I was never destined to be the ‘young actor goes off the rails’ type, up and down the gossip columns. And having a brain haemorrhage that coincided precisely with the beginning of my career and the beginning of a show that became something quite meaty, it gave me a perspective that I wouldn’t have had otherwise.” She pauses. “I’m quite a resilient human being, so a parent dying and brain haemorrhages coinciding with success and people following you in the street and getting stalkers – you’re just, like, ‘Well let’s try and make something sensible of it.’”

It was a decade that contained the very best and very worst of a life, and one of the sensible things she tried to make of it was the founding of a charity, SameYou, to provide treatment for people recovering from brain injuries and stroke. It was only in order to promote the charity that, eight years after her stroke, she finally decided to talk about it, in a piece for the New Yorker. “On the set, I didn’t miss a beat, but I struggled,” she wrote, of returning to Game of Thrones after brain surgery. “Season two would be my worst. I didn’t know what Daenerys was doing. If I am truly being honest, every minute of every day I thought I was going to die.”

It’s remarkable, considering her profile and her regular appearances in the Daily Mail in lovely dresses and grand smiles, that she managed to keep it secret for so long. She didn’t want to tell strangers, “Because it was mine.” She feared, too, that people would “sneer at it”.

It so happened that, the week before I went to meet her, I had a similar (though less dramatic) neurological diagnosis – when I tell her about it, for some reason my voice shakes. She is warm and quick with recommendations, and as she continues she says, “Well, you know, then. You know the worries. That people will think your soul, your movement, your voice, who you were,” was damaged. “It was nerve-racking to share it, to be honest. It always is, when you make yourself vulnerable.” She waited so long to talk about it, because, “I didn’t want people to think of me as… sick.”

There are still days on set when she will quietly pull aside the makeup person and say, “‘I think I’m having a brain haemorrhage. I’m not, I promise, but maybe just put me in a cold tent and we’ll sit down for a second, and I apologise in advance if I freak you out.’ Over the summer I was burning the candle at both ends, and I was with my mate on the plane. And I was like, ‘Dude, I feel really weird…’ But I was fine. It’s hard not to think the worst. It’s hard to think you’re overtired, or you’ve been on Instagram too long, and to realise these might have the same side-effects as something deadly. But the charity evolves with me. I use it. Here’s something else that I feel: maybe someone else feels the same way.”

She talks about the summer just gone with a regretful kind of wonder – it was th e summer after the Game of Thrones finale had divided fans, when she was coming to terms with how the “overwhelming” amount of nudity in the first season had affected her. And, after years of “filling every hiatus with a movie, shit, good or otherwise” (she starred opposite Arnold Schwarzenegger in Terminator Genisys, and as Qi’ra in Solo: a Star Wars Story) she had decided to take a break. Or, the decision was made for her.

“After we did the premiere for the last season, it felt suddenly like I lost all of the bones in my body. And I was in this puddle on the floor going, ‘Maybe this isn’t just the show.’ I’d never wanted to look around and see what we had, because I was convinced it was just going to blow up in our faces. And, well, at the end it kind of did. So I kept my head down. Then, after the premiere, I finally was able to stop, and that was difficult.” She travelled and went “raving with my mates, but that was not fulfilling. So, bloated and exhausted I went away for two weeks with my best girlfriend, [The Good Fight star] Rose Leslie, and it was in this retreat in India that I suddenly got it. This is what stopping feels like. And I was able to finally… be kind to myself.”

All this is recent. All this is really recent, with a new understanding of grief. Her beloved father, a theatre sound engineer, died of cancer in 2016. “The world felt like a scarier place once my dad wasn’t in it,” she said at the time. “There was the referendum, too,” she shudders. “It was the year of everything bad.”

But it was after her lost summer that, “I finally got this feeling. As if, on a cellular level, I’d grown up. And it’s so bittersweet, because I was clinging on to that childlike optimism. Then, when I finally let it go, I realised that was actually quite a heavy backpack to be wearing. I felt like that at the Emmys, too, finally popping my head up from the bunker. It’s as if you can see the actual landscape that you’ve been living in this entire time from another perspective.”

Occasionally she looks at me apologetically, her eyebrows like arrows, to check she’s not saying too much, and then she continues. “It can be perceived as such a feminine trait, can’t it – the responsibility to ‘put a smile on it’. And, and you feel like it’s a defeat if you give in and admit, ‘Maybe it’s not going to be OK in the end.’ But then, if you do, then you have an opportunity to go… ‘and what if that’s all right?’ Death is shit,” she says, dramatically. “It’s really hard and grief is horrific, and yet it is completely and utterly guaranteed. No matter how much Silicon Valley boys want to prove to everyone it’s not. But the finality of death, the absolute certainty of it, I’ve realised, is such a tonic.”

Along with a good stroke, I add the loss of a parent to her list of recommendations. “No! I’m not recommending it to anyone, obviously. But it is something real you can actually hold on to. We don’t look at grief properly. I’m not talking about the random moments of completely overwhelming emotion, I’m pretty in control of that… there was only one time on set where I just physically couldn’t stop crying. It’s the other stuff that we don’t discuss – the functional grief; when your worldview and your perspective on life and yourself changes irrevocably, forever.”

How is she dealing with that? “By realising that there is a framework that life lives within, and knowing when you reach the edges of it. There’s that. And I try to use the shit feelings as opposed to just ‘breathing through it’. It’s like putting my plastic in the recycling bin – it might not do anything, but I should at least try. And then being an actor and having a production company, knowing that the greater understanding I have about life, the greater storyteller I can be. As an actor, you’re always observing – no matter what trauma you’re going through, there’s a wee bit of your brain that’s like, ‘Isn’t this fascinating?’”

Every time I interview a famous person I leave feeling slightly high and slightly sad, because to enter their fabulous world also, inevitably, means you see the shadow of their cage. The imposed disconnect, for instance. And the constant smiling and the many locks. Clarke was catapulted to extreme fame during a period when she nearly lost her mind. She started to find gifts outside her door, from one of many stalkers. One, she says, is extremely unwell, another extremely mean. “The stalker stuff is just horrible because, as a single lady walking around town, I already feel like I’m being followed.”

These stalkers believe they’re having a relationship with her, “which is confusing, because having a relationship with people I don’t know is a big part of what I signed up for. I care about what art does to people. But it carries with it a responsibility, and when you leave your front door you take that with you. And it’s a difficult path to navigate. Because sometimes,” and she’s talking about fans now, the line between the two often being blurred, “you get grabbed physically and your instincts kick in. When you see shock being registered on someone else’s face, you’re like, ‘Where’s the danger?’ And then you realise, oh, it’s me – I’m the danger.”

Her fanbase is due to change shortly, as she maps out her career without dragons. Clarke’s new film is Last Christmas and is based on the Wham! song. While it is a box-office hit, reviews have been… mixed. “The kind of bad,” said Rolling Stone, “that falls somewhere between finding a lump of coal in your stocking and discovering one painfully lodged in your rectum.” It threatens to become a cult classic. Reader, I loved it.

Clarke plays a woman whose messy life, it becomes clear, is partly a result of recent illness. “I was able,” she says darkly, “to bring a lot to the role.” There is a romantic twist, a twist so gooey it may cause diabetes in vulnerable audiences, but there is a second twist, in that this film (co-written by Emma Thompson) could prove to be the most effective piece of anti-Brexit propaganda of the festive season. Clarke (with Thompson as her mother) plays the youngest of a family of first-generation immigrants, dealing with the fallout of the referendum.

“We filmed a scene of a hate crime,” Clarke says, a scene on a London bus where a couple are told to go back to where they came from. “And Emma said, ‘Come on, let’s be honest: haven’t we all witnessed something similar?’” She loved working on this film, in part because of the women in charge, “who recognised that we all had a life outside this movie. You don’t have to have a vagina to do that, but the difference lay in that slight… lack of patriarchy?” And in part because of the intersection between entertainment and what she describes as “meaning”. Something she continues to search for, albeit with regular disclaimers of privilege, and embarrassment.

“The world is scary at the moment, both politically and environmentally. You have politicians pushing people to the absolute limits of their left versus right parameters, and the middle ground that we were all living in before is now wasteland, because both sides are life or death. It feels so much more polarised and extreme than ever. You’ve got 33-year-olds like me asking, ‘Should I bring kids into this world? If I do, what will that kid feel like?’ It feels frightening, consistently. And I’m not alone. I’m leaning hard on Bake Off right now.”

But the fear has made her reassess her work, post-Game of Thrones. “Entertainment is about taking you outside of yourself for a second, which is largely what I think the success of Game of Thrones was. People wanted to see something familiar, but also have that level of separation, through dragons and magic. Escapism is what lots of people go to art for. So, if we can cherry-pick stories to tell people in a shitty time, I’d like to give them something really good. It could make them feel better, or less alone, or make them realise there’s something outside of their front door that they should care about.”

She takes a sharp breath. “You know, I spent a lot of time being like, ‘What I do is all bullshit. I’m completely selfish, a total narcissist.’ And then…” And then the world hit her at a great speed, and she emerged into this new adulthood, and 10 years crawled over her like glittering rats. “And then I realised what it was for. I help provide relief. And that’s worth something, especially now. Right?”

It takes a second before I realise she is waiting for an answer. “Right,” I say, reassuringly. “Right.”

Last Christmas is in cinemas nationwide now

Stylist Hope Lawrie; makeup by Lynsey Alexander at Streeters using Lancôme; hair by Ken O’Rourke at Premier Hair and Makeup using Charles Worthington Volume & Bounce Body Booster Mousse; shot at Chesterton Road at beachstudios.co.uk