Well, no one's mentioned it, but the equivalent of "racism" for gays and lesbians is either "homophobia" or "heterosexism." There's all sorts of debate on which word is more effective.
Anyway, while gay men and lesbians are generally frowned upon in society, gay men tend to have it worse. This is nothing new.
Back in the 1950s, homosexuality was viewed as a mental illness or disorder, a characterization that did not change until 1973 (74?), when the American Psychological Assocation took it off the list, partially in response to the gay rights movement which had been in full swing (no pun intended) for about half a decade.
Back then, it was called "gender inversion"; gay men wanted to be women and vice versa. It is for this reason that we see the roots of lesbianism being a little less stigmatized. "Oh, they want to be men," was the reasoning of the time, which to many of them made sense, considering that men had the power. But for men to want to be women? Sissies!
Unfortunately, the most common reason has already been given (straight men seeing 2 women "get it on.")
In other news:
Organizations run by religious groups with the express purpose of attempting to shift one's homosexual orientation to heterosexual are called "ex-gay ministries," and they are extremely controversial. There are myriad stories of gays and lesbians now in committed, monogamous heterosexual relationships.
"Reparative therapy" is the same thing without the religious bent. Just as controversial. The primary impulse here is that (at least for men) homosexuality is "caused" by a weak relationship with dad that gets sexualized upon hitting puberty. In other words, one's homosexuality is simply a manifestation of other social/emotional issues that went unmet or unaddressed in childhood. Address those issues, and change (according to them anyway) can happen. There's obviously more to it than that, and I've hardly done it justice, but that's the theory, in a nutshell.
FYI, the two gay male founders of the umbrella ex-gay ministry group (Exodus International) actually ended up falling in love with one another. Several key leaders have also been spotted in embarrassing places (John Paulk, for example, was photographed at a gay bar in Washington DC. Paulk is one of those individuals mentioned above--he was a drag queen who became "ex-gay" and got married. There was a Newsweek cover story about them in 1998. I'm not sure what he's up to now--the gay bar incident happened in 2000.)
So needless to say the jury is still out on the ex-gay/reparative therapy issue.
I hope I've clarified some of the debate.
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