Two personal beliefs and their consequences

I am a fatalist; I do not believe in free will. This is because I feel that my actions are controlled by my brain and my brain in turn is controlled by the laws of physics. There is no room in here for independent action.

I also do not believe in the natural value of morality. I do not believe that any actions are in and of themselves inherently right or wrong. While I do in almost all cases act in a moral way (I haven't murdered anyone, for example) I see no real reason to do this.

Because of these beliefs I am ethically off the hock if I kill / rape / steal etc. Not only is it NOT MY CHOICE (because I do not have free will) it's not "wrong" because I don't believe wrong exists.

This seems to me an unsatisfactory solution. What do I do?