I think one of the greatest conflicts that will come about in friendships/marriages/etc is that when damage is done, it is automatically assumed that it is un-repairable. All damage is irreversible, because it can't ever be taken back. You can't ever take back what you've said or done or what anyone else has said or done to you.
But damage doesn't have to be un-repairable. Things may never be the way they once were, but it can be new.
We hold onto the way it used to be, because change hurts us. It hurts that it used to be so easy to get along and love one another; it used to be that we were best friends. It hurts that it is no longer that way; that maybe I am even dead to you.
So bitterness and anger are the refusal to move on. We're mad about how we've been done and with that anger we feel justified to hold a grudge. And we're hurt because something that was so precious was taken from us.
That's when a new normal has to be found. We remember the old normal and reminisce it, but we have to accept that those times have passed. We have to be willing to forgive and move on to the future.
It may not be easy to have something different than what used to be, but at least it's something. It is peace and restoration; the end of strife and division.
Moving on is the only way to really forgive. I'm trying to do that, although my flesh would love to continue sulking and being angry. I just have to trust that God has a plan and that He, the one that can heal, will bring healing.
"Sometimes you have to meet your opponent halfway."