I agree with both posters above. I was married to a guy with a really bad problem with pot and excessive drinking. When you deal with it, live with it, and try to resolve it without the participation of the one doing it......a person reaches a point of no return. I had to make a decision....live with this or start a new life. It's the old saying "A little too little, a little too late". For me, the pain caused by the process of leaving him was less than the pain of staying.
I sincerely hope that he sticks with sobriety and doesn't let this become an excuse to drink again. If he sticks with AA, he'll understand the concept of acceptance. He'll realize that his life can move in a positive forward direction. If her leaving him was the catalyst for his recovery, she saved his life.
gentle hugs
ke