Honesty and thoroughness is key. The more you can get out and go over with sponsor, the more relief you get--sooner rather than later. I was surprised to see that I had so many resentments too--some from long ago....perhaps even forgot about until I started writing. They say in NA that anything you think about is inventory material, whether people or institutions, plus your sponsor will also be able to help you. Better to write more than enough that not enough. We are as only as sick as our secrets. Resentments are indeed poison to us.