[skillyaslig]

Well, my Great-Aunty is a lesbian, yet that was a Life Style choice for her.
The men she had been with were abusive, and harmed her, both physically, and emotionally, thus she chose to become intimate with other women, as women are not as violent (though there are some crazy bitches out there) as men in domestic situations.
By all accounts, she is happy with her partner, though is rather narked that she can't marry her...
But thats not the thing we are discussing.
So you can CHOOSE to be gay, in some sense.
Yet the majority of the time, it is kinda wired in there when you reach the sexual age, because, as Pilot said, when we are little, we are Asexual.