There's a pivotal scene in her memoir, Wild, when a twentysomething Cheryl Strayed is perched atop a mountain. Having eased her battered and bloodied feet from her hiking boots, she knocks over her enormous rucksack, sending one boot tumbling into a ravine. Entirely alone, hundreds of miles from anywhere, with only one boot, she screams, she cries, she swears - but she does not give up. Instead, she throws the other boot after it, duct-tapes sandals to her feet and ploughs on.
In truth, I didn't expect Wild to be my kind of book. As guilty as the next person of judging a book by its cover, I assumed it would be an Eat Pray Love-alike.
Ten minutes into the film version - held, almost single-handedly, by an astonishing Reese Witherspoon, who last week bagged an Oscar nomination for her performance - I realise I'm very, very wrong. Because Wild is not from the scented-candle school of self-help. It's not whiny, schmaltzy, perky or self-pitying. It's a painfully honest portrait of a modern, messed-up woman taking a circuitous route to the right place, by walking almost half of the Pacific Crest Trail (PCT), a 2,500-mile trek that stretches the length of the West Coast between the Mexican and Canadian borders. After seeing the film I read the book; I loved it so much I read it twice. And I'm not alone. Two years after it was published, Wild currently sits at number three in The New York Times bestseller list.
When we meet, the film has opened to acclaim in America and just had its British premiere. The woman whose personal journey lies at its heart breezes into the hotel room, glossy, groomed - her feet killing her. Throwing herself into a chair, she groans as she eases off silver heels and props bare feet on a pouffe. Having recently spent two hours watching the celluloid version of these feet blister, bleed and lose successive toenails, I'm voyeuristically transfixed.
"I've never worn high heels until this month," Strayed admits, eyeing them ruefully. "I'm doing all these red-carpet things with Reese and with certain clothes you just have to wear heels. And I am so not a heels person."
Surely they aren't more painful than her hiking boots?
"It's not lost on me that so much of Wild is about my feet hurting, now here I am promoting the movie and my feet are killing me!" she says with a laugh.
"It's just a different form of footwear that I'm torturing my feet with."
The hotel, the heels, the blow-dry…
It's all a far cry from her "hard-scrabble" childhood. Strayed (the name she adopted after her divorce in recognition of the extent to which she was lost) grew up in Pennsylvania, "a hick from the Northwoods". Her family were painfully poor even before her mother, Bobbi, took Cheryl, her older sister, Karen, and younger brother, Leif, and left their abusive father.
"I spent the first six years of my life in a house with a violent raging tyrant who beat the hell out of my mother in front of us. Countless times," she says matter-of-factly. "But my dad was a sweet-talker. And my mom was 25, she had three little kids and no money. There was very little consciousness of violence against women then. It was still considered kind of OK. But she pulled us out of that and she changed our lives. And we had a very happy life. We lived in a house full of love and joy."
Eventually, Bobbi married Strayed's stepfather Eddie, and moved the family to rural Aitkin County, where they lived in a house they built themselves on 40 acres of land filled with horses and dogs but minus electricity and plumbing. Then, aged 45, she was diagnosed with lung cancer. Within weeks, she was dead.
The impact on the family was cataclysmic. "My family actually ended when my mom died," says Strayed.
"My brother and sister and I still really needed a parent, the way that our mom held everything together. The work she did was invisible, until she was gone.
And then my stepfather, who I loved like a father, he just couldn't be a parent to us, and so he didn't. I tried really hard for it not to end and I failed."
By this time Strayed was 22 and had been married for three years, something she now describes as "crazy". Chances are the marriage wouldn't have lasted, but in her grief she "threw herself in the path of destruction". Promiscuity, hard drugs and eventually divorce followed. Four years later she decided she had to save herself. "When my mom died it was like the only person who had ever loved me that way was gone. And would always be gone. For the rest of my life. But eventually I realised that the real dishonour to my mother would be not to thrive."
She is not "super-close" to her brother and sister - "I love my siblings, and they love me, but it's not like we spend holidays together. I saw my sister last year and I hadn't seen her for 17 years. There's no ill-will, it's just our family disintegrated. Our dad's alive, but we don't have a relationship with him."
Strayed has tried to make contact. "When I completed the PCT, one of the first things I did was track my father down. And I tried a couple of other times but he hasn't changed. Finally, when I was 39, we had a very nasty exchange and I realised I had to let him go. I learnt so much from having him as my dad - about the world, and about myself. So, it's OK."
Strayed is, without question, the most grounded person I've ever met, at one with herself and the grenades life threw at her. It's something she attributes to the months spent alone on the PCT. In 1995 Strayed walked from the Mojave Desert to the Oregon-Washington state border. A mountainous hike through all climes and terrains, it would challenge anyone, let alone a novice with an 80lb rucksack. Physical pain and practical concerns (such as avoiding rattlesnakes and finding water in 50˚C heat) meant she had no mental space for her emotions, and she learnt to bear the unbearable.
Some baggage she shed, the rest she learnt to carry. As metaphors go, it's not subtle, but it's certainly effective.
It was 17 years before she wrote Wild.
In between, she published Torch, a novel about a family pulled apart by the death of a young mother, and Tiny Beautiful Things, a collection of essays from her online agony column, 'Dear Sugar'. What took her so long? "It's not an 'I did this, therefore you should pay attention to me' memoir. It's a book I had to write when I knew something deeper about what it meant to feel lost and find my way back. That anti-Hollywood transformation was the hike for me. Not one big epiphany: 'Oh look, I'm so f- up and now I'm all better.' It was more, 'I'm having a really hard time in my life right now and I have to save myself.' At the end of the hike I had nothing but student-loan debt and 20 cents. And I was completely OK. I was better than OK. Which is not a narrative we hear often, especially with women."
Ah, yes. The anti-Hollywood aspect of Wild. How did a film about one woman and a backpack - with occasional flashbacks to domestic violence, casual sex and shooting up - ever get produced? Strayed laughs. "My film agent [Shari Smiley] told me, 'The only way this is ever going to get made is if an actress attaches herself to it because she wants to play that role.'
"So you need not just an actress who passionately wants to make it, but one powerful enough in Hollywood that she can get it done. Reese was the first person we sent it to. She loved it and called me immediately. And that was it. I was dazzled by her movie star-ness but I got over that within five minutes. Then I was like, 'Why do you want to make this? Why do you think you're the actress for this role?'
"She was totally open with me from the start."
While seeing Witherspoon portray her is "surreal", it's also less than straightforward.
Wild is radically honest. Strayed makes no attempt to portray herself in a good light. When she watches Reese-as-Cheryl having sex with two men in the back alley of a diner, does she wish she'd been a bit less frank? "Not at all. I think that is the whole point of art, to tell us the truth about ourselves. I'm saying, 'This was my experience, this is what happened, this is what I made of it.' The book wouldn't have been successful had I done otherwise.
"Most of us are afraid of [being honest] because we think people will judge us," she continues. "Certainly people have written nasty things about me, but the love and gratitude far outweighs the hate. And you're always going to be hated. Especially in this online culture where you can say anything to anyone without any responsibility."
In the film, the younger Cheryl is played by her real-life daughter, Bobbi, now seven. How did it feel to see her on screen? "It was so powerful. I cried. Especially to see her re-enact scenes with Laura [Dern]. Laura plays Bobbi, Bobbi is named after my mom, Bobbi plays Cheryl. It's so meta! And the scenes with the father…" She takes a deep breath. "He was yelling at her and I kept saying, 'Are you OK?' And she'd say, 'Of course, Mom, we're just pretending!' It was devastating to watch, because… I wasn't. For me it was not pretend."
Strayed met her second husband, the documentary-maker Brian Lindstrom, nine days after she finished her hike. Nineteen years later she lights up when I mention his name. Would they be married if not for the PCT? She shakes her head. "I love him so much, I can't begin to tell you how important he's been in my life. I feel like I walked to him and the life I have now. The person who started the trail wasn't ready to meet Brian, the person who finished the trail was."
Strayed has described her husband as the last person she regrets having slept with. "It's true! We met and connected immediately and so we slept together immediately. Next morning, I woke up and looked at him and I knew I was done [with one-night stands]. So I told him I didn't want to play this game anymore and he said, 'Me too. I really want to be your friend.'
"I thought it was just a line, but he kept calling and we would go for long walks, or tea, or play board-games. We didn't touch each other for six weeks and fell madly in love. The sexual tension was so high that I would practically faint if I brushed against him! So finally, I just took his hand one day… and we knew."
The couple and their children (Bobbi has an older brother, Carver) still live near the northern Oregon section of the PCT. It has become an annual pilgrimage - albeit with less baggage. "Walking is a form of therapy and meditation and exercise for me. Every day I go walking.
"We're going to go for a walk now, I'm sorry," she announces to her publicist as he enters the room. "I'm going to wear my silver shoes so I can write the sequel to Wild, walking around London in heels, and drinking wine. Maybe I'll lose another six toenails."
For a second, her publicist isn't entirely sure if she is joking. Nor am I. But as the prospect of a day of wine and walking with Cheryl Strayed is cruelly snatched away, I can't help feeling more than a little disappointed.
© Sam Baker / The Sunday Telegraph Stella
'Wild' is now showing in cinemas