(LifeWire) -- It was the sock in the jaw that finally did it.
An online survey found 1 in 4 people regularly retreats to a spare room or sofa to get a good night's sleep.
"We were lying in bed spooning when he had an elbow spasm and punched me in the jaw," says Barbara, a 55-year-old graphic designer from Lansing, Michigan, who asked that her last name not be used.
"I was already so sleep-deprived from his twitching and snoring that I was psychotic. After that, I just told him, 'It's all over, honey.'"
Barbara's husband of 22 years, who asked not to be identified, moved into another bedroom. They're among many loving couples who -- because of snoring, restless legs, opposite schedules or other nocturnal difficulties -- have decided to sleep apart.
A growing trend
How many couples sleep solo in a double bed?
A 2001 random telephone survey of 1,004 adults conducted by the National Sleep Foundation found that 12 percent of married Americans slept alone; a similar 2005 survey of 1,506 people found that number had jumped to 23 percent.
In addition, a March online survey of 1,408 couples conducted by the Sleep Council of England found that 1 in 4 people regularly retreats to a spare room or sofa to get a good night's sleep.
The preference for separate spaces has even begun to affect home design. According to the National Association of Home Builders, there's been a steady increase in the number of requests for "two-master bedroom" homes since 1990, prompting the organization to predict that by 2015, 60 percent of all custom upscale homes will be built with two "owner suites."
Married to a 'jerk'
Paige Barr, 35, a New York City casting director, says she sleeps apart from her husband, Daniel Craft, 37, for two reasons: his sleep apnea and what Kramer on "Seinfeld" called "the jimmy leg."
"You know when you're just about to fall asleep and you jerk yourself awake? He does that like 36 times an hour for seven hours, 200 times a night," she says. "His hand will jerk or his leg will flail, plus he snores super loud."
Barr, who's lived with her husband, an online content provider, for five years, say they've never been able to sleep together.
"If I were forced to sleep with him, I would break up with him and kill myself," she says. "I need my sleep."
Bad for marriage?
Although many couples say separate rooms have been a blessing (Barr says her friends are jealous of her sleeping arrangement), Minnesota clinical psychologist and marriage counselor William F. Harley Jr. warns sleeping separately could spell trouble.
"Whenever I see a couple wanting private time -- they want to be alone, they want their own friends, they don't want to feel like they're joined at the hip -- my immediate question is, 'What is it about being together that bothers you?'" says Harley, author of "Love Busters: Overcoming the Habits that Destroy Romantic Love." "My feeling is that sleeping together is a very, very important part of being integrated with each other."
Jason Holloway, 29, an estimator from Greenwood, Indiana, who slept on the couch for about six months while his wife, Rebecca, was pregnant, agrees that separate beds have a downside.
"I had the TV, I had the dogs with me," he says. "But I didn't feel 100 percent like I was part of the loop. I felt removed from the whole situation."
A new kind of marriage
But Stephanie Coontz, author of "Marriage: A History" and director of research and public education at the Council on Contemporary Families, a nonprofit research organization, says sleeping in separate beds in order to get a good night's rest is reasonable and revolutionary.
"In the early 20th century, there was this idea that when you were married, you shouldn't have a separate existence," she says. "But in the last 30 years, we've come up with something absolutely revolutionary that says there's more than one way to do marriage. ... People are saying there are lots of ways to have a happy marriage and even a good sex life."
Alisa Bowman, a 37-year-old freelance writer from Emmaus, Pennsylvania, says that sleeping apart from her husband Mark, 42, a few nights a week -- something that began five years ago when she was pregnant -- has made their marriage stronger.
"I'm a better mom and wife when I'm rested," says Bowman, who says she's always had trouble sleeping with another person in the room. "I also think it makes you appreciate each other more."
Sleeping apart hasn't hurt Scott Hepburn's marriage, either, says the 29-year-old copywriter from Charlotte, North Carolina, who sleeps alone five nights a week because he's a night owl and his wife, Carolyn, is an early bird.
"She teases me about it, but it's never been a major point of contention in our relationship," he says. "We actually have a lot of fun with it. When I do something stupid, she threatens to punish me by making me sleep in the same bed with her."
My place or yours?
Couples who keep separate rooms may get plenty of sleep, but are they getting anything else -- like sex?
Absolutely, says Barbara, wife of the sleepy slugger.
"We create time for each other," she says. "We have 'dates,' and to be honest, it's pretty romantic. We're both awake for one thing, as opposed to people who think they've been intimate but they've slept through the whole thing. Now it's like, 'My place or yours?'"