Getting your needs met does not make your a horrible person... it sounds like it's making you an unhappy one, though.
It sounds to me like there are other significant issues present aside from the sex in your relationship, and it may be time to take a break from it. Get away for a while to evaluate what it is that you really want. I know how important your husband is to you, but doing what you're doing is dangerous, and may ultimately end your marriage anyway.
Please keep us posted on what you do!