You cannot keep making yourself upset or angry about things that have happened in the past. It is so tempting to revisit old hurt feelings but this doesn’t help soothe the past, it only hurts the present. It brings things up that were supposed to be laid to rest, forgiven, and forgotten. People change, people grow. You have grown yourself. Therefore, stop reverting back to and thinking of your past self and past situations. Don’t ruin the future with things from the past. Recognize that they have happened and move on.