Hi Lewis, you are doing the best you can in a difficult situation and I get the feeling you are not enabling her except where it's unavoidable. No doubt the children love their mum despite her behaviour. I was in a similar situation in my teens, I hated my parents drinking but I still loved them.
I think you are putting up with a lot for the sake of the children, and possibly you'll have to manage the problem until something gives. It's likely her drinking will worsen over time and you may have to take more drastic action.