Something I have personally learned is that when people are hurt badly by an experience or a person they tend to cling to it and even begin to identify themselves with that pain and that experience to a large degree. It is not possible to stop forming your identity around that pain and that experience until you forgive the person or persons and let go of the experience that caused your hurt. It has to be released before it will stop hurting you over and over. It is the only way to really care for yourself and heal. Purposely going back and revisiting painful experiences and holding onto hurt feelings is dangerous. You are recreating that pain anew each time and this is only destructive and will lead to anger.
Memories may resurface, but there is no need to dwell in them. Very painful memories can tend to flood us with overwhelming amounts of emotion and it seems to only grow stronger over time when we allow ourselves to stay with the thoughts. Our perception of the memory is not the same any longer. It begins to take on a life of its own and this is how we can form our identity around it. When children have started forming their identities around painful memories, like loss, then it is even more difficult for them to comprehend how to break this cycle and heal. This understanding must come as an adult for them, and it will be a struggle as they continue to cycle back through the pain, thinking they are doomed to live in misery forever. This thought itself perpetuates the cycle and leads them into more difficulty.
Not continuing on with thought processes or speech patterns that follow this cycle can help break it and that is an important thing to do for healing to begin. As long as a person continues to feel that they were wronged, or that something should have gone a different way than it did, that person will continue to feel miserable. Railing against your loss or your suffering in anger and sorrow, no matter how long you do it will never change what happened. It only makes feelings of suffering and anger stronger and the experience of loss or suffering is essentially being relived inside. This can only lead to further harm. It also leads to us creating many incorrect perceptions based on the flooding of pain from previous life stages and previous states of perception. It becomes very difficult to see the peace and happiness that can be found in your present if you are looking at things through a lens of altered perceptions fostered by revisiting painful memories.
However, starting in the present moment and recognizing good things with gratitude is helpful and begins the process to healing and breaking the cycle of going back to pain. Focusing on the small things, like breathing, gradually brings awareness back to what you are feeling right now. This awareness can be used to acknowledge and accept the feelings as they come, learning how to feel them and let them pass without holding onto them. Emotions about very difficult events arise and these emotions are not easy to feel without dwelling, especially at the beginning. Taking five or ten minutes of quiet time in which you can sit alone and let these feelings come is helpful. This is short enough to not be difficult to find in a day and to not allow time for ruminating on the feelings that come up. Each one comes, is recognized, and then is let go. This begins to allow for sorting. The recognition will also come that thoughts and emotions arise but they also fade to the background. This can give a sense of peace that the true inner self is not truly as rocked by external events as we tend to believe.