  Eight years. A friend of mine and his partner broke up yesterday after being together nearly eight years. Another friend of mine has broken up with his boyfriend of a year and a half. Maybe long term, all parties will look back and see these as good decisions, but it's still sad.
I urlLink wrote here a month ago about the moment of realization that a relationship is over... and I was thinking of one of these relationships at the time. They're not easy under any circumstances, and while we as friends should do all we can to support our friends in relationships, I don't feel any obligation to encourage friends to stay in relationships that aren't working. How you calculate whether yours is working or not is up to you. But I'm relatively hard-nosed about the pursuit of happiness and I've learned the hard way that if you're not happy and the situation can't be fixed, then it's time to get out.
One can take that to a selfish extreme and that's not good. But, too often, people stay in less than good or just plain bad relationships out of inertia or fear of being single. And too many gay people on the sidelines are quick to pounce and point to a breakup as a sign that gay men either just can't have a good relationship or they're too promiscuous to want to stay together or they just can't see how good they had it, etc. Have you noticed that 1) these people are nearly always single themselves; and 2) they're losers? The gay community's rampant desire to be accepted by the straight world has led, predictably, to some rather fucked up views of what is a successful gay life.
The Successful Gay Life is not the aping of a model provided by the majority culture; and it's not defined by the incessant carping that comes from inside your minority culture. It's what you define it to be. 
