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.

If your heterosexual partner is failing to fulfill your needs, fantasizing over another heterosexual partner is usually considered the norm. Whenever I fantasize, it is always over women and never men, correct, I've never been sexually abused.
You exhibit signs of one whom has been sexually abused, I pray that I am wrong.