I don't have any words to explain his choices for you, because you and I are not alcoholics so we can't understand what he's thinking or why he's thinking it.
It sounds like her standards are pretty low so he won't have to try very hard to meet them. But you and your babies deserve a better life than that mess you just described.
I guess this is where the one day at a time thing kicks in. Just keep moving forward for today. You and your babies don't have to deal with any "crazy" today.