The Treehouse is Naomi Wolf’s first book about a man rather than the sisterhood and it is a love story in its way. I ask her if it has been hard to find men who live up to her dad. She looks at me in amazement and bursts out laughing. “No. I’ve had plenty of men who I adore — appropriately.”

Attracting men has not been a problem for Wolf, with her sparkling eyes, mane of brown hair and ready smile. They were sometimes the wrong sort but there is adventure in that. Then came the years of seemingly blissful marriage to David Shipley, an editor at The New York Times and father of their two children.

She was surely the luckiest feminist, people said enviously, just as they had when she published The Beauty Myth in her glamorous twenties. Their marriage is over, though, and they are in the process of divorcing.

“It is truly nobody’s fault,” she says. “We had a wonderful 10 to 12 years. It is really sad, but everything is working out as expected.”

Out of respect for his privacy, Wolf would rather not talk about the reasons for their separation. But whether or not he had a hand in what she calls her midlife crisis, she clearly hit a wall.

It is a familiar one for women of her age, who often feel overwhelmed by the demands of children, marriage and career. But Wolf, 43, insists it is not the whole story.

“There is the issue of the multitasking professional women with families, but you can take a vacation or go to the gym and recharge. My working life is relatively easy compared to many women because I’m self-employed. That’s huge. And I’m not poor. I don’t think that’s what led me to the crossroads.”

It was more a case, she says, of the “‘Oh God what am I doing with my life question?’ It is only in silence and solitude that you can listen to what’s wrong and what is supposed to be right.”

For working women some things never change. At one stage during our interview she tries touchingly hard to answer my questions while juggling her childcare arrangements. After several phone calls it is obvious things are not working to plan and we have to dash across town to pick up Rosa, her now 10-year-old daughter, from school.

Taking the time to build a treehouse with her father at her cottage in upstate New York helped Wolf to straighten out her priorities. “Honestly, if I hadn’t taken that journey I don’t think I could have ended up this serene. I really am happy.”

She is dating, she confesses with a smile. “It’s someone lovely,” she says. “Everyone’s different and I wouldn’t want to compare, but it’s really lovely, it’s nice.”

One of the lessons Wolf’s father taught her was: “You can’t avoid suffering in your life, but you can avoid suffering about the suffering.”

She feels it applies to her own fractured home. “I can’t give my children what I wanted — an intact family — but I can give them the most loving, unintact family.”

It helps that David is a “wonderful, wonderful father”, with whom she shares custody of Rosa and Joey, now five. “I feel there is this bubble of love and protection around the children,” Wolf says.

As far as possible, she tries to follow her parents’ example. “I’ve got to hand it to my parents. They were quite traditional for their time about emotional security — and permissive about the imagination.”

They were hippies, but they were also Jewish. Growing up in a radical neighbourhood in San Francisco, Wolf recalls, “We’d be lighting the candles on Friday night while everybody else was in their hot tubs smoking pot.”

Sometimes their very permissiveness got a bit much. “They were so annoying when I was a teenager because you couldn’t horrify them. I’d say, ‘What if I turned out to be a lesbian and they’d say, ‘Oh sure, honey’.”

Her father had a temper and could be suffocating in his own way. “He is a free spirit, but he is a man of his generation, and there are reasons I grew up rebelling against the patriarchy,” Wolf says. “I needed to break out and find my own voice.”

It was not until her thirties that she learnt he had a secret. “He made at least one gigantic mistake; monumental, some might say unforgivable,” she explains in her book. “He fathered a child in 1950, knew about his son and never told us about our half brother.”

That son was Julius, who happened to read an article about Wolf in a magazine when he was 38. He was struck by the accompanying picture of her father; an old black and white portrait of a bearded man of 38, who looked just like him. He had known the name of his biological father and suddenly realised he had found him.

Father and son met for the first time under the clock at Penn station in New York. Two years passed before Wolf’s father rang her and said, “I don’t know exactly how to say this honey . . .”

“Of course I was angry. Secrets are not good in a family,” Wolf tells me. “It was one of those unfathomable things. I’ll never get those years back when I could have known my brother.”

Her dad once told her other brother Aaron — the one she grew up with — that the secret of a happy life was simple. “Do everything your wife asks because they don’t ask for that much.” It was so perceptive of him, Wolf remarks, because “women are always asking for reassurance”.

I am persuaded by now that her father hasn’t put her off the other men in her life. If anything, with his big heart and big flaws, he has made the feminist in her more open to them. But I would think he is a tough act to follow.