Well, not exactly... It seems there's never anyone who's actually gay in a Bioware game, just bisexual. And it didn't help that Zevran was just amoral, horny, and non-discriminating, which isn't the healthiest way to portray gay relationships. A lesbian relationship with Leliana had the potential to be much more wholesome.
By the way, I juuust finished my second playthrough of Mass Effect 1. I slept with Liara as female Shepard, mostly because Ashley was on my squad. Did the same with male Shepard because Kaidan was on my squad (and Ashley annoys the hell out of me).