Just one question (which may help you figure out things): you say that you have always been attracted to girls for as long as you can remember. Is this true for guys as well (i.e. have you always been attracted to guys)? I am asking because it could be that you want to be with a guy because of social expectations (it's the 'norm' after all), while you are with a girl because of sexual/romantic attraction. If you are truly bisexual, then this probably won't help, but it could be worth thinking about.