I can relate. "That's your parent! The Bible says honor your father and mother!"
Bible aside, I do honor them, in that they suffered abuse without access at the time to professional help, as in turn did I. When I became an adult and realized I was fast having the save nasty personality, I got myself into therapy. Some therapists were pretty awful and one actively did more harm than good (low cost, sliding scale; whole other story), but I kept at it. And when I end up going full no contact, with the parent with whom I'm minimal contact, whether that's before they pass from this earth or not, I' may end up back in therapy, abd if not, there will be plenty of shadow work, ongoing, for maybe the rest of my life. And that's just fine. That parent has money and Medicare part B, so there's zero reason they can't choose to get better, but it's just easier to blame everyone else.