Is there anything behaviors that are inate in people (i.e. instinct)? For some reason you seem to think that repeating your “behavior is a choice” line it somehow makes it true. Are you saying that there are gays who are born attracted to their own sex, but they could resist (behavior)? If so, this is a more reasonable choice. If you are saying that all gays choose to be attracted to their own sex, then you are using a low powered processor.
Desires are inate. There are survival desires, i.e. the need to eat, drink, sleep. But no one dies from not having sex. No one dies from not stealing, lying, murdering.
Sorry, there is no excuse for giving in to a desire to do something that is wrong in the eyes of God. And same gender sex is wrong.
If you want to do something that is wrong simply because you have the desire to do it, don't expect everyone to say "Well, he couldn't help it."