FRIENDSHIPS can become a little tenuous when climbing the ladder to success, especially if you become rich and famous and suddenly find yourself surrounded by sycophants and hangers-on.

But top author Jane Fallon and her long-term partner Ricky Gervais still have the same friends as before they became rich and famous.

Yes, they have some celebrity pals - including Jonathan Ross, and Fallon enjoys friendships with other female fiction writers, such as Adele Parks and Lisa Jewell - but the couple's remained loyal to those who were there long before that.

"You make a choice about staying with the people you've always been connected with or not... I was 46 when my first book came out. Having those changes in your life when you're older is probably a good thing, because you know who you are and you're more settled in your life," Fallon has said.

Plus the fact she spends much of her time in their home in London's Hampstead, writing her novels - often in her pyjamas. "I don't even know where I'd stumble across someone, let alone convince them they'd want to be my best friend," she says. "You just don't come across proper, deep, loyal friendships very easily later on in life."

But it was Fallon's personal experience with someone she thought was a great friend which gave her the idea for her latest novel, Faking Friends, a contemporary tale about an actress who returns from LA after losing her job, only to discover that her so-called best mate has been having an affair with her fiance in her absence.

"We'd been close friends for years and she knew that my lifelong ambition had been to write novels. We hadn't seen each other for some time as we'd both been busy at work, and I happened to see her the day after I got the news that Penguin were picking up Getting Rid Of Matthew (her debut novel, published back in 2007). I said to her, 'Oh my God, you won't believe what's happened to me!' - and she couldn't even fake being happy for me for a second. She just pulled a big face and said, 'Oh my God, it's not going to be chick lit, is it?' In that moment I just thought, 'You're not really my friend'."

She dismisses the notion that finding true friends in the cut-throat world of TV - she was an award-winning producer behind hit shows including This Life and Teachers - may be a tougher prospect than in other industries. "I don't know that it is a cut-throat world. I always enjoyed it and if you're good at what you do, you'll do well. It is a 'talent will out' industry."

She now feels she really knows who her friends are. "You come across those real, genuine friendships so rarely in your life and they are so precious, you know the people who really have your back, who love you unconditionally and aren't your family. You don't stumble across those people very often."

So what does she look for in friendships? "You want someone who has a similar sense of humour, similar sensibilities and I really like the balance of someone that's spiky and funny but also really kind. Ricky is clearly my best friend," she says.

They met as students at University College London, and her career was on the rise long before his - but they were never competitive with each other.

"When I was moving up, it was good that one of us was earning. I never felt I had to put pressure on him to have a big career, and he never felt overshadowed by the fact that I was doing well," she has said.

Despite their success, Fallon says she's never experienced forced friendships from hangers-on who want to be seen with them. "I don't really put myself out there that much. I have got a good radar for when someone's bullsh***ing me," she says. "I'm lucky. I've got a really good group of friends. I don't feel the need to go out and forge new bonds."

Her friends used to reveal the nitty-gritty of their lives to her, but not any more as they know it may end up in one of her novels, she quips. Instead, they quiz their own friends, and go back to Fallon with stories about other people's relationships. Her own life with Gervais, however, has been pretty free of such trials and tribulations. "Luckily my own life is uncomplicated, which lets me really enjoy other people's complicated messes!"

She and Gervais never wanted children, although she wrote an article last year saying that she regrets that she'll never have grandchildren. Today, she says she was joking when she wrote it.

"I can see in theory it would be a nice thing. I mean, when you say you don't want kids, people ask you who's going to look after you when you're old. Maybe when I'm old, I'll think, 'Oh damn, I should have had a few kids to look after me - but there's no guarantee they would, anyway'."

  • Faking Friends by Jane Fallon (Michael Joseph, £7.99)