Hey,
I can 100% relate to this. I’m 30 and my Dad has been an alcoholic it turns out most of my life also. He is also at a stage now where we are just waiting for it to kill him as he has completely given up on life. Unlike your Dad mine was occasionally physically abusive to my mum and they are no longer together but he lives with his elderly mother and this enables him to drink still.
I completely understand your feelings of anger and then heartbreak at the same time though.
Can you see if there is a support group you (and your mum) can join, I joined one local to me about 6 months ago and it is the best thing I have ever done. Speaking with others in a similar situation and learning about enabling and other things has been so beneficial for me. I also started going to art therapy, which was a safe place for me to feel like I can get all the anger and hatred I feel for him at times out, so it wasn’t just whirling around in my head anymore. I was in a bad place a few months ago but I feel like a different person now and the guilt I had has gone now which was one of the things I struggled the most with.
Natalie