It's struck me that the best explanation for all those people saying "homosexuality is a choice" is that for them, it is. IOW, the reason that they think people can suppress their same-sex attraction as an act of will is because they do precisely that themselves... and if they can do it, so can other people.
They're also equating orientation and feelings with sexual activity. A heterosexual man can refrain from having sex with women but he's still heterosexual. A homosexual man can refrain from having sex with men but he's still homosexual. I can force myself to have sex with a woman (note the word "force") using a lot of fantasizing, which makes me about as straight as a corkscrew.