It’s a little random, but sometimes, out of nowhere, I’ll get really mad about something that happened quite awhile ago.
The person I’ve loved the most, also hurt me the worst nearly two years ago. I’ve moved on, so has he, and he’s now one of my best friends. While I’m not “in love” with him, I don’t think there are many people in this world who I love more than him.
But sometimes, for no reason at all, I remember what happened. And I get really, really angry and hurt all over again.
I’ve forgiven him, but I haven’t fully adopted “forgive and forget.” That’s when I realized the other day, that as humans, we CAN’T forget. It’s just not possible. But you know who DOES forget? God does. Isn’t that amazing? He can forgive AND forget. And that’s exactly what He does. He doesn’t hold a grudge. Ask for forgiveness and BOOM! You got it. And God won’t ever have a day when He thinks about that time you messed up.
As far as the east is from the west, so far has He removed our transgressions from us.”
Psalm 103:12
summitcitysingle 
I sympathize completely, I’m in a very similiar situation and struggle with the same feelings you just described. Its not easy, not easy at all, but as I keep my faith, I’m learning that it does get easier