Like many happy couples, Rob Siemsen and Willie Brese of New York City have discovered the secret to a perfect partnership. Bound by mutual respect, they have nurtured a connection over the past 13 years that is fulfilling without being smothering. And though the relationship has been off and on since the early nineties, they are now on stable ground. Their foundation is an ability to communicate, no matter the impediments. "There is nothing that is out of bounds in terms of what we can talk about," says Siemsen, 36, a graphic artist who first met and lived with Brese in graduate school. "We talk about anything and everything. The significant thing with Willie and me is that we never get sick of each other."

As it turns out, Siemsen and Brese, 33, who is also a graphic artist, are both straight men. They also happen to be roommates in a brownstone apartment in Brooklyn, New York, which they have shared since 2001. The arrangement has less to do with saving money or extending adolescence than it does with companionship. "I've lived alone once as an adult, and the quality of life wasn't there," says Siemsen. "Life is just better when you have someone to talk to."

If Generation X ever needed an epigraph to stamp at the top of its declaration of independence, it could do worse than that one. According to Ethan Watters, author of Urban Tribes: Are Friends the New Family?, marriage is no longer looked at as the crucial step that signifies adulthood. Pursuing a long-term roommate situation is one of the ways young men indefinitely delay marriage while still enjoying some of its social benefits, forming their own "nontraditional families, marked by a consistency of affection." Whether it's a long commitment to one specific roommate or a series of different mates over a number of years, what was once considered a brief oat-sowing stop on the road to settling down has become for some a long-lasting, emotionally fulfilling oasis unto itself. And nobody is apologizing for anything.

"Having a successful roommate experience is a lot like having a spouse," says Jon Cirome, a 32-year-old marketing executive in San Francisco who has lived with Brad Smith, 30, for three years. "Both have to do with trust and mutual respect." Before hooking up, Cirome and Smith, a software salesman, had been serial roommaters—Cirome has had ten roommates since college; Smith, five. They met through a mutual friend, and hit it off on their "first date." Both men love music and found a mutual outlet in their late-night jam sessions, with Cirome on acoustic guitar and Smith on keyboard. And both are competitive triathletes, training in tandem on many a chilly Bay Area morning.

The key to their success, they say, is a commitment to sharing. Unlike male housemates fresh out of college, who tend to be cash-strapped and possessive, these two don't label their breakfast cereals. "We share toothpaste, shampoo, even the food in the fridge," Cirome says. "But we don't have to constantly talk about it. It is very much like a marriage, where you're not discussing every little thing you're buying."

While both men are securely heterosexual, Cirome admits that the way they interact often raises eyebrows, especially in their adopted hometown. "In San Francisco, this leads people to make assumptions," he says. Friends and family members have also questioned the arrangement, as have, predictably, the women Cirome has dated. "Sometimes girls will get that look, like, 'What are you doing?'" Cirome says. "It signals that I could potentially be that frat guy."

So why keep doing it?

"When you find the right person, you don't think about how strange it may be to be living with a roommate in your 30s," Cirome says.

Ironically, those who spend years shacked up with another man may be making themselves better marriage material. According to Dr. Jan Yager, author of Friendshifts: The Power of Friendships and How They Shape Our Lives, long-term cohabitation can help forge the frat boy's polar opposite: an emotionally mature adult. "Living with a roommate is a training ground for marriage to the nth degree," she says. "You learn to give and take, and how to get along with someone in a day-to-day situation."

Sometimes this spirit of cooperation can even involve major investments. Doug Brandenburg and Brett Gorney have been living together for four years, three of those in the two-bedroom townhouse that Brandenburg, 34, bought in 2002. Brandenburg, who is in the restaurant-service industry, was considerate enough to find a place with a home office so that Gorney, 33, would have adequate space to run his consulting business. Though Brandenburg could have gone solo, Gorney provides a sense of emotional security (if not wifely surrogacy). "A lot of my friends are married," Brandenburg says. "I'm not there yet, but why should I have to sit home alone? At least I'm not coming home to a dark, cold, empty house."

For Ethan Watters, Brandenburg and his cohorts are representative of a new breed of single man. "This is another way to explode the myth of bachelorhood," Watters says. "We are social creatures who desperately need rich layers of social interaction, and these roommate situations provide another person in your life. It's the rare bachelor who leads the solitary existence that we sometimes imagine them having."

Yet as much like marriages as these arrangements can be, the men involved have not walked down an aisle or vowed to be together "until death do them part." In other words, separation is an eventual reality. Andrew Edelson, 36, and Jon Glickstein, 35, lived together in a 2,500-square-foot Chicago house for five blissful years, until that fateful day Glickstein decided to move in with his girlfriend of nine years. At the same time, Edelson decided to quit his lucrative sales job to follow his dream of being a movie producer. He packed up and headed west. And while the two are still close friends and business partners, the ending did take a toll.

"The breakup was mutual and amicable," Edelson says. "Yet as much as we knew it was the right moment for us to take the respective next steps, there is a deep sadness in realizing that a special moment in our lives has passed." He is now living in Santa Monica and has no intention of finding another roommate. Glickstein, it seems, is the one that got away.

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