For me...I think that a big chunk of healing from deep resentments is just the simple fact that we get to a place that we are willing to allow certain things to become past/ancient history.....and just put it down....because it no longer serves us...
My life experience has shown me that the anger/resentment can be a good motivator to take care of ourselves, at certain times....
and, it can take a period of time...sometimes, a long time....to be able to set that baggage down......
It can't be forced down our throat too much.....