Have you sought professional help? You did not mention that in your letter. You have suffered for many years with these issues starting when you were a young girl. These issues have only grown progressively worse and have gotten to the point where it is difficult for you to control your actions or keep yourself safe.
You likely need help to learn how to control your emotions and behavior. It could be as it was for so many others, that you were never taught or shown effective ways to handle difficult situations. Maybe your parents or role models did not know how to control their emotions or behavior. If no one shows you how to deal effectively with your anger or you watched a parent explode in rage in reaction to a difficult situation, then it can be a struggle for you to do things differently. You may have to learn how to act appropriately.
A good therapist can equip you with alternative strategies for dealing with your anger. He or she can teach you how to behave in situations and may be able to help you to make better decisions. You need guidance from a trained mental health professional. You shouldn’t continue trying to handle these matters on your own because based on your letter your only solution has become one of self-inflicted pain and injury.
You’re at the point where you need to reach out for help. Please consider seeking professional help and if you feel that you are going to hurt yourself, go immediately to the hospital for assistance.