Salukigirl, you make good points and you are right. I'm afraid of my abusive father, but once I did stand up to him and push him away, because he tried to take my son from my arms. He is 5'11" and over 300lbs. I'm only 5'4" and 120lbs. It's amazing the strength that can come over you when you need to. This is nothing like that though. I was just protecting my son.

My bipolar friend used to get into terrible physical fights with her mother, her mother fought just as hard as she did.

My husband was also abused by his parents, he began to fight back when he became a teenager. He was protecting himself.

I suppose these people were fighting back, the parents were hitting them as well, and OP didn't say the mother was fighting back at all. But everyone is different with their feelings and how they would react to their abuser. I don't care about approval or love from my father. I'm done with him. But I wish I had the guts to physically hurt him.

It is possible she was a great mother, but it is possible she wasn't. I'm not trying to advocate the abusive man's parent abuse. I'm just saying she might not deserve so much credit for bringing him into the world, because she may not have been the best mother. He may have got this way on his own, because of others, or he might have gotten this way from his mom. Your point are most likely right, but there is other possiblities. You are right though. She shouldn't stay to find out.