Sexuality isn't a state of being, it's a state of mind. Something happened in your life and based on your experiences as a child, your brain makes a chemical decision to decide whom you're attracted to. I.e. A homosexual has a chance to be gay because they may have had an older brother(s) or lacked a father figure and had an overbearing mother. The environment and people of your childhood indirectly decide who you are. Don't like being bi? Blame your parents.