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.
Sounds like you are good enough though. The dates you've gone out with don't seem to appreciate you.
Have you tried the "being friends first" thing? This worked out for me. I got to feel for myself what kind of personality the other person has, and overtime I became confident enough to pursue something more because I knew the person already, and she knew me.