I always suggest forgiveness... because dwelling on stuff holds you far more captive than it does the other party. Now, saying that..., forgiveness does not neccessarily mean reconciliation.
Also, really forgiving a rotter... can be cleansing. Revenge just leads to bitterness, and no one is worth the toll that will take on your psyche.
So, forgive and walk away.... Really, who cares if he gets it or not... isn't your problem any more.
LGF