I hear you. I am sorry that she was never able to make ammends for her cruelty.
My mother was extremely physically abusive when angered, but she was also very loving and supportive. I just think about her getting married at age 17 and having three babies a year a part and I cut her some slack.
The physical violence eventually stopped as she matured. She is very kind to my children and we can actually laugh about her maniacal rages now. I was born in the 1950s and most of my friends were getting clobbered too.
I am not trying to make light of this inexcusable behavior. My children have never been struck in anger and it breaks my heart to see children being handled roughly.