It's not a choice, it's just the simple fact that I'm straight. Though I can look at a man and know if he's ugly average or handsome, it makes no difference to me. Either way there's just simply no appeal. I've never been uncomfortable with homosexuality, it just does nothing for me. I can watch two hot women together and find it appealing, I can watch two hot men, and there's nothing. I'm not disgusted or repulsed in any way, I'm just completely unmoved.
What if its a hot man that looks more like a hot woman? This is the only reason why I think you're being dogmatic. Such people exist, and you're not really taking the possibility into account. You're just assuming that your named sexuality trumps all. I don't think its so clear cut is all.