Well, I put bi, because I have always felt that way. I had crushes on boys when I was in grade school, then saw a naked woman and decided that women are hotter than men. Then decided I liked boys again.
Ever since I found out there was a Bi, I chose that. But I recently tried to fool around with a girl, and realized that I didn't like girls anymore. But I feel that I just wasn't attracted to her. Ha ha. (By the way, I am married (to a man) and have a child.)
I go between curious and sexually bi. Not because it is the 'in thing'. The only thing I wouldn't do with another female is marriage, for that, I'd have to say I want a man. But in which case, I do like females but my pull for males is stronger than for females.
Kinda pisses me off when people are oging "Oh yeah I'm bi, but I would never kiss a girl or anything lolololol" =__=