Generally, when there is abuse, it is the wife who is abused by her husband. Wife abuse is one of the main reasons for women to be seen in hospital emergency rooms. When women hit or scratch, it is often in self-defense. If the abuse isn't physical, it isn't really so serious. We know that words can wound more deeply than blows.
Emotional abuse kills the spirit.
Furthermore, physical abuse is always accompanied, and often preceded, by emotional abuse. At the extreme, emotional abuse can cause physical illness, loss of the will to live or death by suicide. Abusers are generally unpleasant or angry people. I could certainly tell if someone were an abuser. If the abuse is kept quiet, it won't affect the children.