I never made a gay sim in my life. Actually, come to think of it, I did make a few of my female sims bisexual (mostly to become witches, you had to be in a good relationship with another witch to do that) but in the end, they would get married to a man and have kids. Then it would get boring and I'd start to lose interest. Oh, actually, now that I remember, I made a male sim in Sims 2 castaway stories and got him to have a boyfriend, so I actually did... It happened only once, however.
I remember playing Sims 2 and 3 when I was younger and I always had my normal files, but then I had that one secret one with the gay couple lol I always loved that one the most. Either that one or the one where I trapped a sim that I didnt like, for whatever reason, in a small room with no doors or windows and watched it suffer > Lol I've done some pretty weird stuff in that game.