Bisexuality Support Group
Bisexuality is a sexual orientation which refers to the aesthetic, romantic, and/or sexual attraction of individuals to other individuals of both their own and the opposite gender or sex. Most bisexuals are not equally attracted to men and women, and may even shift between states of finding either sex exclusively attractive over the course of time.
Maybe what you need to focus on is the idea of openness and truthfulness between you. You sound like you're more open about things than he is. And that's just a personality thing.