Sounds very platonic, masochistic, weak, or (all 3) Christian Virtue..
Rather, we should treat others as you wish to be treated... And then when their response is sure, "treat others as you have been treated." Love those who deserve love, and destroy those who deserve wrath. A law of basic human nature.
That's just rhetoric people tell themselves to convince themselves they have power they actually don't.
You know what happens when you tell an enemy you forgive them? They respond, "Excellent! I'm no longer responsible for doing THIS," and then they repeat the behavior you sold out your self-respect thinking you could score a gotcha moment over.