I lost a "best friend" to verbal abuse --- their own. I found I could no longer allow them to use me as the reason for their claim to "victimhood". I miss them anyway.
Verbal abuse is anything you say to a person in order to hurt them on purpose, or ignore them in order to hurt them, whether or not the abuser is aware of it. Verbal abuse is when you pawn blame, shame and other things for which you should be responsible onto another person.
Verbal abuse is 'ATTACKING' a person through words: stinging, biting words. The verbal abuser instead of communicating their anger in a constructive manner (which would be to keep the focus on what is relevant) instead strikes out verbally at the other person: calling them names; cussing; screaming; threatening; intimidating; any means possible to establish their need for control. Usually they never see this as their problem, it is always the other person's problem. It is common for a verbal abuser to say things like "You MAKE ME act this way". They don't take responsibility for their own behavior and can not even understand the concept of taking responsibility for their own behavior, because they are in their own view: 'the victim'.
Only if the abuser truly wants to change, will he or she change. What the abuser first needs to have the motivation to change. Once they realize their motivation, then they must learn what they are doing wrong. The majority of abusers are angry at something. They must come to terms with the anger. Then combining motivation and terms, they are ready to begin the long road to recovery.