I had a small chance to talk to him a couple days after her anniversary. He knows this has divided his side of the family & his mom has pushed him ever since to just forgive & move on.
He will not.
I don't think she has the right to ask that of him or understand his feelings & he refuses also to look at reason.
So I told him that he's been hanging on to this anger for a very long time. What does he need or want that will let him move thru this?
He said he wants details! He wants to know why, why this slip in judgement occurred & basically why this family member is not in jail for what he sees as a crime.
Ultimately, what I think I hear him saying, is that he wants revenge!

He wants an eye for an eye. He wants this person to publicly be humiliated and destroyed and maybe then he'll feel better.
He does not think that it's fair that this person has been able to move on in their life. And he just won't let go of these feelings.

In certain places of my mind I can understand his reasoning and his anger, but to me that leads to very black-and-white thinking of no forgiveness or second chances.
And this makes me sad because I see this as a primate thought process? Something that is very simple. Funny he doesn't live his life like that.
In a way I find it very fake & a bit simple mindedness. I've really lost respect for him.