I think people are born bisexual and the make subconscious choices based on the pressures of society. I have no question in my mind about being bisexual. But I'm also a hypocrite: I would never date a girl who is bisexual, because that means they also sleep with men, and men are so dirty that I'd never sleep with a girl who had slept with a man.
When you think about it, we actors are kind of prostitutes. We get paid to feign attraction and love. Other people are paying to watch us kissing someone, touching someone, doing things people in a normal monogamous relationship would never do with anyone who's not their partner. It's really kind of gross.