since when is protecting yourself being mean....its called SELF-DEFENSE. If I have to harm someone in SELF-DEFENSE its NOT being mean they are just getting what they deserve & whst they asked for because they treated me in a way that required me to respond that way. All he cares about is what he gets from you of it wouldnt be done in secret. NOTHING virtuous is ever done in secret like that.
Any DECENT relationship is an equal partnership with equal respect & equal love....that is not what you are involved in & it will NEVER be that way.
The only way for you to stop this is to cut all connections.
What are you REALLY getting out of this relationship that makes you refuse to let go?