He started drinking again,should I get his family together for an intervention?

He will continue to drink if you keep allowing him. What that means is taking him back, allowing his excuses etc. He just spent seven years in jail and he will go back it he continues to break his probation. But, he just spent years in jail and now comes back to what? A record, no job, starting a new life, feeling like a failure. These are all reasons he may drink, but they are not excuses. Try talking to him and see if he will go to support groups... fact is, his PO can find him drinking just as easily as you can... unfortunately jail doesn't give you the tools needed to change your behaviors, so once your out, you have the same mindset, but now it's how not to get caught, but he will. It will just take time. I would talk to him and try and find support for him. BUT if he doesn't stop you need to cut off all contact with him... and tell his family. I would rather someone I love be safe and get help and be mad at me then keep enabling them in fear I may lose them.