Children of abusive parents can react in very different ways.
My mother's father was an abusive alcoholic. Her older sister stood up to him and got knocked around along with their mother. Her younger sister acted out and got knocked around as well. My Mom became the placater, the perfect child who never attracted his attention when he was angry. Every payday when he came home drunk, my Mom would either sleep on the floor under the bed or in the closet so he wouldn't see her. She still (at the age of 79) tenses up when voices are raised and tries to calm everyone down. Knowing what she went through, I can't say she's wrong. It's not how I would (think I would) react, but I can understand why she is the way she is.