You must take care of yourself, or you are no good to anyone else. Don't ignore how you feel in hopes things will improve or it will go away. You feel that way for a reason, and if you can do the work to figure out why, you will be so much better for
Don't hold onto anger. Don't blame others for your mistakes. Apologize for your mistake, learn from it. From that point on, it's really out of your hands.