How much have you actually lived out some of your fantasies? Have you found that experiencing masochism in reality you still want it as extreme as you fantasize about?
I have kind of the opposite problem. I love sexual sadism, and my girlfriend is a masochist. But she doesn't want it nearly as extreme as I do. She wants some spanking and whatnot, but I'd bruise her and hurt her a lot more if she were into it.