I knew a "Gold Star" lesbian. It's funny though, cause she's 'straight' now.
The way I figured it is, if there are plenty of people who start out thinking they're hetero and then sleep with a person or two and realize they're gay, then there have to be at least a few people who start out thinking they're gay and then realize their hetero.
Granted, the Kinsey scale says no one is really 100% straight or gay, we're all something in between.
But being proud of never having slept with the opposite gender is just as silly as being proud of never having had a gay experience.