I've got a friend... help?

So I have this friend who I have known for a very long time. He has had some trust issues in the past big time, not only with is female companions, but also with his male friends. He always thinks people are out to get him. We've gone through countless fights over the years because of him falsely accusing me of doing something, or having ill intentions in some of my actions.

I do like the guy, when he lets his guard down he's a great friend and a really good guy. I feel bad for him in a way as well because he cannot keep friends or girlfriends for long because of his trust issues. These trust issues stim from his father being a drunk who would sneak into his room and steal money/things to sell and shit like that so he could go buy more drinks. So i know where it comes from, we have talked about it in the past and I thought we finally had it worked out.

Today I find him saying things to someone I am fairly close to saying, he can't trust me, can't leave things laying around when i'm around, and that my "whole family" is like that... (kind of ironic coming from someone who had to hide shit from his own father). Anyway I am again fed up with this...

I would love to be able to break through to him finally so he knew he had a real friend when he looked at me, but he keeps going back to his old way of thinking and its really starting to wear on me... What would you guys do?

>>10
No the original was WWJD so he/you just copied that