Sorry to necro but:

When it comes to homosexuality, despite facing a lot of hatred and bigotry, I have really never seen anyone, no matter how bigoted, make the claim that it doesn't exist.

Actually, most homophobes believe that homosexuals are secretly bisexual, meaning that they are capable of being attracted to the opposite sex as well.

I know these misconceptions are frustrating, but the fact is, bi people haven't come together politically to try to dispel these false notions, and often are the ones spreading the misinformation.