I feel sorry for you who are facing divorce and who's significant others are still drinking. My ex is not, thankfully. I really believed that him quitting would solve all of the issues. It did not. Deep down, and sometimes on the surface, he is just an ass. A self righteous, mean, hateful ass. He recently married a like-minded woman. Good luck to them.
Anyway, a while back, I felt blasted on here for not picking my kids up and leaving when the ex was physically abusive to my middle son. I completely understand why people were so upset with me, but... He left no marks. The State Attorney dropped the case. He was verbally and emotionally abusive, not "really" physically, in the eyes of the law. He would've had 50/50 custody of the 3 kids and I would not have been able to protect them 50% of the time. In this state, the kids wanting to be with one parent more, really has no bearing. You must prove the majority of 20 specific points that they are better off with you and even then, it is up to the judge. That's a gamble I wasn't ready to take. Instead, we stayed. I protected them the best I could. My oldest graduated high school and enlisted in the military and then my prayers were answered. He found someone new. The divorce process began, he tried coming back, but I did not even entertain the thought. This was our new beginning. My 2 other sons were a bit older and could stand up for themselves. It was rough and my anxiety went through the roof due to PTSD from the abuse. My faith in God got me through and I am now a stronger woman than ever before. The kids are happy and my house is a peaceful place. I have a wonderful man in my life whom my sons adore. He is respectful, kind, caring and gentle...
My point is, only YOU know what is best for your situation. Pray for direction and hang in there. I found the light at the end of the tunnel and you will too.