Toss in self-loathing or secret lives such as Ted Haggard
Ted who?
Oh this isn't the sarcasm thread...
There are several dispicable reasons why someone choses to homophobic, xenophobic, misogynistic etc, i mentioned just a few.
Yours, self loathing can have different aspects. I loath myself for my inability to see words properly, my husband loathes his cancer, neither of which make us homophobic. But yes, considering the majority of the population is not in the 14% (or so) who are fully heterosexual then for various reasons (i listed a couple) they might develop a self loathing towards their own gay feelings.
Again, secret lives can be secret for different reasons but again, yes i should think harbouring a secret homosexual relationship would affect a person