Hi Nixx. There is really nothing you can do. It is all about what you are willing to put up with. You are on your guard, the radar is up, and we do that not only to weed through the truth or the lies, but also to protect ourselves. I know I have walked in your shoes.
You are right, an alcoholic does not go to a bar if he is in recovery. A crack head does not drop into a crack house for a little visit to see old friends. It is a disaster waiting to happen. But these are his choices and he is going to do what he wants to do. Addicts lie all the time, it is part of the disease, part of their survival. In a way you have to think about how simple they think we are, for offering us such lame stories and thinking that we will fall for it.
The sad thing is that for some of us who actually believe or attempt to believe the lies is that in the end we start doubting ourselves. This is when the insanity walks in and the road starts to become bumpy.
Trust is the most important thing in a relationship. The foundation of a good and long lasting life together. Without it there is nothing. The question is are you willing to except all of him just the way he stands before you today? I am asking this because this may well be what you will have ten years down the road.