That's a sweet one Brad.
Please tell your friend that he's not alone, I wasted years of my life after I came home from Viet Nam. The money that I spent on booze, drugs, lawyers, court costs, etc. would have bought a nice house and a couple of cars. Each of us has had to find our way back down in our own way. It's never easy and it's always painful. Be sure to let him know that there is help available and that it's not pity, it's something that he earned the hard way through his service.
Ay VA hospital should have offices for Veterans Service Officers from the VFW, American Legion and the DAV. Any one of them will be happy to help him, that's what they're there for.
If that doesn't work, PM me and I'll give you my phone number to give to him. Sometimes just talking to someone else who's been through what you have can help. I'm no expert, but I've paid my dues.