I am so sorry you're being exposed to all of this. It's a very difficult situation and, honestly, your dad sounds like a very difficult man. If he said he blacked out, he probably has problems you can't do anything about. Going back and changing his story to "she deserved it" is fairly common as people try to reconstruct a memory.

It's okay to detach from your dad as much as possible, to step back and to live your own life. Even though he's making a mess of things, it's also okay for you to love him anyway. But just because we love someone it doesn't mean we have to get involved in their problems or do anything to fix them. Sometimes love means accepting them as they are and letting them go as we get on with our own lives.

He and Ann are both adults, although she is very young. It's not your job to save them. I hope you can put all of your energies into taking care of yourself and having the best life you can away from your dad's chaos and abusive actions.

Stepping away with love is not an easy thing to do. But it is the best thing. I wish you a good life.