I don't think it's the "bi-cycle." Often I lose attraction to men altogether, never ever to women, I have to try to get it back and I don't usually find myself attracted to men, maybe characteristics of them but not them, I often mistake feeling nervous for being attracted to them, if that makes sense. When I have a crush on a woman it lasts for a while or even years and is very deep, whereas my male crushes aren't even really crushes or anything, they have a good trait or something I deem a good trait, like being tall and I think that's good or I find them interesting. I have no idea if this makes sense sorry. I could definitely be misreading everything though, since I go to an all-girls school, but I still have been in male environments, like when I had a part-time job, sports, and family friends. A lot of my crushes on men were based on what other people had crushes on and what I should/who I should have a crush on. I remember my first crush on a boy was made up because I heard another girl had a crush on him and I wanted to be like them, so I faked it till I made it.