He was a nasty drunk and I bet he will be again. It took (in this order) rehab, 2 DUI's, separation, loss of job, house arrest, jail, house arrest, hospitalization, 1 dv arrest (not physical, but still DV), losing joint custody of his older kids, and therapy to get him sober. Why TF would he drink again?
one might also ask why TF you thought he would not? i mean he kind of has a resume on his drinking career. he is doing what he has always done, demonstrably, tangibly.
you can stop hanging yours and your kids future on what someone else may or may not do, and just do what it best for you.