But you know what? It's okay. It really is.
Not to the point that what whoever it was in whatever realm did what he/she/it/they did.
But to the point that it's done. Over with. And that that person can move along, move forward, and take the lesson part of it to heart, evolve the spirit, resolve to avoid doing it again, and feel better knowing (remembering) that a future point in time is the fading of the mistake. You don't have to have people like you, it's okay. Or if it wasn't that, it doesn't have to be everlasting regret/pain/sorrow. Just... learn. Learn the lesson. Figure out what it is. Find what it is. Be sad as you need to, but don't dwell. If it's anger that ails you, face what is making you angry. Make resolve with it. Make resolve by admitting what needs to be admitted to yourself or others, by learning how to see what makes you feel unsettled, by looking at the resources around you to help see yourself in a removed light, by experiencing the terrifying turn-around that comes with trying to change and the successful peace that comes after the cycle is completed. Understand that all things growing require some kind of painful metamorphosis--life was designed that way--but find rest and peace that all these things were meant for you to have. All these things were meant for you to find, for you to learn, for you to embrace, for you to grow. Find comfort in the end result. Keep hope as a candle flame to whatever darkness is hurting/plaguing you and remember that it is only God above that gives these things to you, for it is He Who created the mustard seed, which is tiny and deceivingly insignificant, but whose seed bears and produces the most enormous tree. Even the seed of a soul-less tree must break in the ground to grow. How much more must we, humans, intricate, beautiful and complex, break the same way in order to grow?
May peace be with you.