Jay McInerney interview: Story of his life

"The pig was sleeping in the bed. With you. In the marital bed. With you and your wife.""Well, yes," I say."You've been coming to me for more than a year, trying to come to terms with your guilt about the break-up of your marriage, and this is the first time it's occurred to you to mention that the pig was sleeping with you in the bed?"

JAY McINERNEY is something of an expert on such a mnage trois, for this conversation comes from a short story, Sleeping with Pigs, which he's about to publish and which he admits, with his trademark lopsided grin, is deeply autobiographical.

The narrator of the story is McSweeney – McSwine, to his ex-wife – who is "droning on" to his shrink about his failed marriage to a gorgeous Southern belle and her penchant for creating menageries, indoors and out, on their lavish Tennessee spread.

It's an exchange that McInerney has almost certainly had with his own therapist. For he admits that his third marriage was over when his wife, the Southern belle Helen Bransford, introduced her newest pet into their bed, insisting that the pot-bellied pig sleep with them.

"Oh sure, it became too much for me. Terrible! I could have done without that. Wouldn't you, if your husband installed a pig in your bedroom?" asks the American novelist, once notorious for his cocaine-fuelled, brattish behaviour and hedonistic lifestyle. "My former wife is a very eccentric woman," he continues, pausing for dramatic effect, before adding, "which is why I still love her."

Shortly after the pig snuggled between the connubial sheets, in 1999, McInerney moved out of the bedroom and eventually out of their Nashville ranch. Of course, like McSwine in his story – one of a dozen in an accomplished new collection, The Last Bachelor – McInerney had been a serial adulterer, but that was not the reason he and Bransford split up.

"We'd our own problems, all by ourselves," he sighs over lunch in New York's Gotham Bar and Grill, a smart Greenwich Village restaurant where he's a regular. It's just around the corner from the Fifth Avenue apartment he shares with his glamorous fourth wife, the heiress Anne Randolph Hearst, whom he married in 2006.

"Basically, the break-up with Helen was my fault; I admit it. Now, though, we're real friends. We go on holiday together with our kids and she's a great mother. It's an odd ex-marriage, but a good one." They have 14-year-old twins, Maisie and John Barrett McInerney III. His face lights up when he speaks of them, telling me proudly about Maisie's prizewinning poetry. He thinks she will inherit his literary mantle since she writes so well, while his son is not remotely bookish. "But there's time," he says.

The "zeitgeist author" – his description – of the million-selling classic first novel Bright Lights, Big City, McInerney famously captured the dark underbelly of the greedy 1980s world of New York's libertine yuppies. He was dubbed "the next Scott Fitzgerald". Overnight, he became the enfant terrible of American letters, a superbrat among the era's literary brat packers: Bret Easton Ellis, Donna Tartt and Tama Janowitz. Ellis still calls McInerney "the Jayster", describing him as his "toxic twin".

But enfants age. On January 13 he will be 54. He is, though, still tall, dark and handsome, with an unfathomable face, thick dark hair, on which the years have scribbled in silver, and startling sapphire-blue eyes. He's also very happy.

He married Hearst on 21 November 2006, at the 21 Club in New York, the former West 52nd Street speakeasy redolent of society money, swank and steak. Former mayor Rudy Giuliani officiated. Hearst, granddaughter of legendary media magnate William Randolph Hearst – the model for Citizen Kane – is the younger sister of Patty, who was kidnapped by revolutionaries, brainwashed, then imprisoned for her part in a bank robbery in 1976. Today, the Hearst family fortune is estimated at 3.5bn; it includes the magazine empire, which publishes Cosmopolitan, Harper's Bazaar and Esquire.

They met at Nell's, the former 14th Street nightclub, in Manhattan, in the decadent 1980s, when (he grimaces), he was probably out of his skull on Bolivian marching powder. He has no memory of their first meeting. "I thought we met at a party, but apparently that was the second time, although we did become friends. Somehow, our timing was never quite right. I would call to tell her I had just broken up with someone, and she would tell me she had just gotten engaged."

McInerney takes his duties as a father seriously. As well he might, for his children were "wrestled into existence". Helen Bransford was 43 when they married – seven years older than him – and had suffered several miscarriages. They had the twins with a surrogate mother and donated eggs. McInerney is the biological father. "I got fatherhood the minute I saw them and held them; then I got to know them and I'm still getting to know them," he says. "They're the greatest love of my life."

In 1993 he published his novel Brightness Falls, which fulfilled the promise shown in Bright Lights, which had been disastrously filmed with a miscast Michael J Fox. "That book was my claim to fame, but it almost wrecked my life," he says. "This stuff comes back to haunt you. Of course, I've had to tell my kids about their father's colourful past, that I was a bit of a poster boy for coke.

"My daughter has read the stories in The Last Bachelor, a couple of which are semi-autobiographical, and she loves them. If they want to talk about all that stuff, then I will, but they don't seem that interested."

Settling down for the fourth time has, however, not stopped McInerney partying in some style. He and Hearst had just had a very late night, he tells me. A wine buff, he can remember every wine he's ever drunk, although Hearst drinks only vintage champagne. "I've never had so much champagne in my life," he says cheerfully. Their high-profile friends range from Uma Thurman to Moby and Candace Bushnell. "Oh yeah, I still like to party. And I still have my moments."

The Last Bachelor is McInerney's first collection of short stories since the excellent How it Ended (2000). The new stories are immensely assured, peopled with his usual cast of characters: unhappily married Manhattanites; cheating screenwriters; wanton, high-maintenance society beauties; and rich men lost in long relationships with cocaine. The shadow of loss, loneliness and Catholic guilt hangs over many of the stories, alongside the events of 9/11.

Born in Hartford, Connecticut, McInerney is the eldest of the three sons of a Catholic family (his father was an executive with a paper company). He attended about 18 schools in the States, Canada and Europe, one of them in Surrey, between the ages of six and eight, where he got the most red stars in his class for academic achievement and the most black ones for behaving badly.

"I've been getting black stars ever since," he laughs. "I sure had a lot of discipline problems. In Vancouver, I blew up a school toilet with a cherry bomb made from a small stick of dynamite. I guess I was looking for attention."

• The Last Bachelor, by Jay McInerney, is published by Bloomsbury, priced 12.99.