Biphobia is the dislike or hatred of bisexual people.
While it seems less common than straight out homophobia, it's refrenced to a bit in gay communities. Biphobia comes from these misconceptions:
-Bisexual people are more slutty or more likely to cheat
-Bisexual people are never satisfied in mongamous relationships
-Bisexual people are just straight people who like playing around with the same sex to be different or to get attention, but have no real attraction towards the same sex
-Bisexuals are just closet gays
-Bisexual girls only do sexual things with girls to get attention from men
-Bisexual men have uncontrollable desires for sex and are full of STDs
-Bisexual people are not picky or choosy about who they date or have sex with
These attitudes aren't spoken outwardly much, but are implied. Some bisexuals have reported feeling shunned in some LBGTQ rights groups, since some gays and lesbians feel like bisexuals are not as comitted to the gay rights struggle as they are.