But the key to a happy relationship, according to Ricky Gervais’s partner Jane Fallon? The author, who has been dating the comedian since 1982, credits his ‘n’ her loos - and ‘friendship’ - for the couple’s continued domestic bliss.
Miss Fallon, one of Britain’s biggest-selling writers, also says the pair have not yet married because neither of them can be ‘fussed’.
"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.
"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. 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.
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... 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.
But top author Jane Fallon and her long-term partner Ricky Gervais still have the same friends as before they became rich and famous.
The couple, who have homes in London and New York, met as students at University College London.
While Gervais went on to find fame transatlantically - first with The Office, and then Extras before hosting the Golden Globes for three years - Miss Fallon has established herself as a hugely successful writer.
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! I mean, when you say you don't want kids, people ask you who's going to look after you when you're old.
Her latest novel, Faking Friends, has received almost unanimous five star reviews on Amazon, and been described as ‘chick-lit noir’.