I'm christian (but forget you I won't argue with you about it just believe what you want)
and I don't give a crap about gays getting married.
People are gay. Let them be gay and marry other gays. Some people are in love with members of their own gender, so let them be married.
For sake of argument, let's say there's a gay guy, who wants nothing more than to get married and live the rest of his life and eventually die with his spouse. Well, if he can't marry other men, he'll probably end up marring a woman just for the sake of getting married. And now, he's in a totally meaningless marriage because he wants to be with a man, and he'll probably end up cheating on her.