Yuck...I HATE gossip and, quite frankly, I couldn't care less whether Tom Cruise is gay or not. That's HIS business and, if he is, he wouldn't be the first gay to get married to hide it from the nosy public.
As for marrying someone half his age, the reason is simple...it's much simpler to control someone who is still starstruck and young rather than someone who is older and used to the scene.