Same can be said by a smoker, or drug addict; and the reason is because you're addicted to the (very small; YES, very small amount of pleasure you're getting from it).
It's an addiction; and you know the first step in getting over addiction;
ACCEPTANCE
I could understand if there was something wrong with you; and you were ugly, and a social reject of sorts, and prefered to masterbate than to actually go out and get some women.. but you don't fit into that category.. so the sooner you say bye to this bad habbit, the sooner you'll be enjoying yourself more (sexually)
I'm not patronizing; I don't judge, don't feel like i'm looking down on anyone; I talk about this stuff to everyone, including my brother.. this is what male-to-male advice is all about.. so just take that first step to change..