It’s a typical weeknight. I’m bedded down with my boyfriend, about to drop off after a long, tiring day, when he turns over. I had been hugging him close — what’s the point of sharing a bed if you're not entwined, at least at first? — but then his shift in position wakes me up. I don’t just slide back to where I was, as a more robust sleeper would. No, suddenly I’m rudely awake, seething with frustration.

I have not had one good night’s sleep sharing a bed with any man I’ve ever been involved with — including my current boyfriend of eight months, whom I love, and with whom I keep trying. For a while, I insisted on lying at opposite sides of the bed — not touching, and even under separate covers — while I tried to pretend I was on my own. I didn’t sleep then, either. For five months, he slept on the sofa during the week and we “practised” sharing a bed at the weekends, when I didn’t have to get up for work. But practice didn’t make perfect — or even improvement.

The solution is nothing short of separate bedrooms — it’s the only way I’ve ever slept well with a man under the same roof. Apart from exhaustion, the biggest burden of my inability to share a bed is the sense of freakery and meanness. Society would have us believe that being involved with someone leads naturally to the ability to sleep well with them. How can someone be so heartless as to want the sex but spend the rest of the night toute seule? On many occasions, I’ve surprised men by my perfect ease with sex followed by one of us sleeping separately. Such behaviour doesn’t cut it with my boyfriend, however, and if I want the sex, I have to share the bed.

Things are changing, though — led by a movement in the States. A survey by the National Sleep Foundation in 2001 found that 12% of married Americans were sleeping alone; by 2005 it had grown to 23%. The New York Times recently cited a survey of builders and architects in which they predicted that by 2015, 60% of custom-built houses would have two master bedrooms. Gopal Ahluwalia, of America’s National Association of Home Builders, observed that this was a “market-driven demand that’s going to continue”.

The designer Diane von Furstenberg is a shining example of a woman in a loving relationship who likes to sleep apart from her husband. She sleeps above her shop in New York, while her husband lives at the Carlyle. This, she told Town & Country magazine, is because “he respects me so much”.

We have a way to go in Britain before separate bedrooms are a socially acceptable arrangement, but it’s happening. The posh and royal continue to sleep separately, of course. Think of Prince Philip and the Queen; or Tim Burton and Helena Bonham Carter, who have their own (attached) houses. Ask around and everyone knows at least one couple sleeping separately in pursuit of a good night’s kip — they just won’t be comfortable talking about it. Even the bohemian parents of a friend of mine, who live in a large house in Chelsea and lead a lifestyle of lavish society dinners and creative work that yields riches, won’t admit socially that they sleep separately.

Usually, it’s one person who needs the arrangement because they’re a lighter sleeper or the other snores. Patrick Miller, a history fellow at Cambridge University, and his girlfriend of three years, Karen Violet Shaftesbury, a postgraduate researcher, have adopted a separate sleeping arrangement. “I petitioned for separate rooms because I hate other people’s jiggling when I want to sleep,” Patrick says. “Also, she snores terribly, and I am more neurotic, so it takes me longer to drift off — and the snoring really gets to me.”

Before they lived together, they put a separate mattress next to the queen-sized one on the floor and used separate duvets. Shaftesbury wasn’t keen on separate bedrooms at first, but has finally come round. “Patrick will usually snuggle with me while I fall asleep, then sneaks out to his room. I used to miss him when I woke in the night, but it’s not fair to deprive him of a good night for the brief moments I’m awake.” Both deny any erosion of their relationship through the arrangement. “It’s just a logistical thing,” Shaftesbury says.

Neil Stanley is a sleep researcher at Norfolk and Norwich University Hospital, and an evangelist for separate bedrooms. He’s always insisted on his own bedroom, with the best sheets and bedding he can find. “We’ve been sold a myth that we have to share a bed or else our marriage is doomed,” he says. “But people who are more tired are more miserable and have a higher rate of divorce.”

Jill Dansa, 49, a wealthy, single hospital consultant, living in Belsize Park, north London, says the bane of her last few relationships was sleep deprivation, caused by sharing a bed. “I ended up not being able to stand the pressure of it,” she says. “Okay, if it was an issue between us, we could work on it, but the persistent sense was that it was dysfunctional on my part.”

“Sharing a bed is just a cultural norm, with no science behind it,” Stanley says. “Posh people have never done it. It’s a mark of wealth to sleep separately — it should be aspirational.” In Britain, bed-sharing is a relatively recent development, entering the mainstream in the late 19th century. Sensible Victorians are said to have wailed about the intolerable cruelty of having to share a bed. As late as the 1970s, twin beds outsold doubles (remember George and Mildred?). It’s only in the past 30 years that adults have been expected to sleep in a bed that provides 9in less space per person, when divided between two, than a child’s single.

Stanley sums it up succinctly. “Sleep is the most selfish thing you can do, and you can’t share it.” Amen to that.

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