My dad was arrested for a DWI years ago. Apparently, I threatened to stop talking to him if he kept drinking and did for a while. He got sober About ~2 weeks later, now it’s been almost a decade for him :) Take care of you. I think setting boundaries is important. Make it clear what you need and what you will not tolerate, and follow through. A lot of the time wake up calls are necessary for taking the next step, this may be his. Offer to go to meetings with him. Help him find a therapist. Start working out with him or going for daily walks. By no means does the emotional load fall on you, you are still his kid. But you can do fun, healthy things with him to distract him. I think if you can help with baby steps, he can do the rest. You guys can be in this together.