Why is revenge seen as a negative thing?

I understand if you’re religious, why it would be. Revenge is to make someone pay for their wrongdoings to you, get even. Give them what they deserve, what they had coming to them. In Christianity, everyone deserves hell without God, so it makes sense that revenge is distasteful or sinful.
But for everyone else, (general public) why is it so socially unacceptable? Specifically in a situation like cheating. A person who cheats steals things like time, love, and innocence. These are all things you can never recover, never get back. But when someone retaliates through destruction of property, sleeping with someone (after their relationship, their best friend, father, fiancé, exc…) telling people what they did, or any creative way; it’s seen as bad, irrational. Especially when it comes to property… materialistic items that you can always buy again. Why are material items seen as more valuable than love? It’s disgusting. Senseless. Pathetic. Sometimes hate is valid, and the only way to sate it is to try to get even close to what they did to you.
I see often people see an evil person doing an evil thing as not as bad as a good person doing a not as good or close to as evil thing. Doesn’t make sense. Why are good people bad for getting back at evil people who did an evil thing? The good person isn’t going around doing evil to good people as the evil person has. This Isn’t exclusive to cheating, but I see it most often with this. Common sense is dead.
Why is revenge seen as a negative thing?
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