I am so sorry, Doug to learn of the abuse you grew up in.
What it comes down to is we have to take responsibility for ourselves and only ourselves. I said some harsh words in a moment of anger; the words may not have been the best choice, but the feelings were and are there, and so that is what I am going to address. For me, that does indeed mean removing myself from him.
The fact that he wants to encourage my sister to drink as soon as she gets off work to take the edge off, screams to me that he is not doing any work inwardly. During the day when he is sober, he isn't asking himself some tough questions or examining his drinking, if he's happy to push the bottle to her (she's a doctor and isn't a habitual drinker). He didn't learn from my own battle with alcoholism; not my DUI, not all that I lost, the struggle, the pain. So he has a long way to go at 67. It's his journey. He has been lucky (or has he?); he hasn't lost anything directly as a result of his drinking. His family stuck around, he still has his career, his house, never suffered public embarrassing moments - save for those reserved for his immediate family, which are frequent and vivid.
I accept his shortcomings as a father; that he just didn't have it in him to be the father I as a child would have loved and adored. But I will be damned if I am going to sit quiet while he verbally abuses my mother with drink in hand, bringing that same abuse I endured as a child into my nieces' upbringing, and stay around through it all.
He may call me ungrateful. I call it self-love and accountability. And I won't apologize for it.