Abuse
Note what Lee H. Baucom says in Save the Marriage:
“I have but one caveat: I cannot encourage persons to stay in an abusive relationship. If there has been any physical abuse, protection is most important. Being in the relationship is dangerous, and I cannot condone a marriage that has physical abuse. If the abuse is emotional or verbal, the abuse MUST stop if the marriage is to survive. Abuse makes a relationship of equals impossible. It is based on power and maintaining a power differential.”
This Psychology Today article provides some advice and helpful links for those wanting to help someone in an abusive relationship or for someone in an abusive relationship.