This is a simple matter of just controlling yourself. I don't believe that you can have "such a powerful urge to have sex" that you cannot control it. There are things you can do to help that urge. You may be confusing the urge with other things.Yes, there are several "castration drugs" that you can take, but maybe that is a little drastic. Just don't get those urges!! You are in control, so you can tell yourself what to think about and what to avoid. It's really not that hard at all.