Nar-anon Boundaries, Trust Not doing very well with these?

I am a new member of Nar anon, I am trying very hard to follow the program and an glued to my SESH book. My addict is my 35 year old son, he over dosed last March and it nothing short of a miracle that he is alive. He is married to an addict and they have too kids. I have separated the addict from my loved one in my mind and so it is a lot easier to handle the anger . I am 60 and on disability, so I have a very small income. Every month he ends up getting most of it, he pawned my laptop, that I let him use. He borrowed money at the beginning of of May saying I would get it back when he got his unemployment last week. Than he claims to have lost his card so I have to wait till he gets a new one. I found out last nite he never lost his card and got the money and its now gone. This kind of thing happens often. If not with anger than how, when I realize he has screwed me once again, am I supposed to call him on it, or just let him think I don't know. he claims hes clean, but where would the money be going. He does not pay his bill. He will wait until the power is off and than call, and for the kids I will pay it. I don't think I will ever be able to trust again. So what do I do when I catch him in a betrayal next time. Thanks