Lotdot19, my thoughts and prayers are with you and your family.
It's so hard to stand by and watch someone you love destroy themselves, their lives and wish there was something you could do.
Sadly, the only thing you really can do is nothing. That sounds mean, but like someone mentioned earlier-until he is forced to face the consequences of his actions, nothing is going to change.
My dad is an alcoholic. Has been all my life. When I was 25, he lost his job, lost his home, lost his car and my brother kicked him out of his home. My dad called begging for a place to stay. I thought I was helping him, and took him in. I did everything I thought was the right thing to do, but really all I was doing was making it ok for him to continue with his behavior.
After several months, and the wonderful people here, I was able to realize that my dad wasn't going to change because there was no reason for him to. As long as he knew that I would be there to 'fix' things, he would continue the same behavior.
I finally told him he had a choice- leave or go to rehab. The choice was his. If he was homeless, it was because that was the decision he made. I gave him 24 hours, and I stood firm in that.
It was the hardest thing I have ever had to do. But, I also knew in my heart it was the right thing to do.
The best thing you and your family can do for him, is to make him face the consequences of what he is choosing to do, and for you and your family to take care of yourselves.