You're opposed to murder?? But why would that be? Because its ........ MORALLY wrong perhaps? And who taught you that?? That's the point, one's morals, as Kimba accurately referenced, are what you're brought up with, regardless of religion, although religion does play an integral role. So, you can opine that someone else's morals are twisted, such as believing that homosexual behavior is immoral, but that'd be a judgment opinion...as in you are JUDGING SOMEONE ELSE. That's NO DIFFERENT, that someone judging someone else's actions on what they've been brought up with
At the end of the day, choosing to be attracted to someone of the same sex is no different than choosing someone else's spouse. Both are based on sexual urges. Kind of along wanting something of forbidden fruit. You shouldn't have it, based on a moral upbringing, so it makes you want it all the more. Some choices, less moral than others. Murder probably the worst moral choice...as in amoral