I brought up MLC with him, but he was more focused on H's drinking and having to hit rock bottom.
I am very interested on why you think it's MLC? The beauty is that if it's MLC or not MLC the way you handle it is the same.
Stella my exw's brother was/is an alcoholic. Spent time in jail for 3 dui's. If you were to meet him you would think he was a great guy. 95% of people on this planet could get 1 dui. To get 4 means you make really bad decisions and just don't give a flip. My ex BIL wasn't a horrible guy, he just made many bad decisions in life and only cared about himself. Those types of people live chaotic lives and never are content with a sense of normality. To have peace in your life you are going to have to let him go. If 4 duis are not rock bottom I hate to fathom what his rock bottom might be.