The school counselor isn't the psychologist--Am I correct about this? Do you see a psychologist? When you are a minor (under 18 in the United States), when you see a psychologist or psychiatrist, the parents have a right to be informed about your treatment and this can complicate treatment if the parents don't understand or are causing a problem for the child that they don't see.

That they got your parents involved when you asked the counselor not to creates a situation where it is harder for you to feel free to talk to the counselor anymore. Even with a psychologist, it is hard to get the help you need unless you trust the person you are working with. If you do not have confidence in the people helping you, I understand your desire to "go it alone" and there is merit in trying to find solutions that don't involve a psychiatrist which would likely prescribe medication.

However, if you still can't let go of the past, my recommendation is to consider finding a professional of some kind that you can trust in a way that you can open up to them about what is going on. It could be a therapist or psychologist rather than a psychiatrist if you are not wanting to take medication though medications are helpful for some. However, there are other ways to manage compulsive thoughts, etc.--sometimes just getting into the habit of not thinking about the past by immersing yourself in new habits can slowly turn things around. Remember, thoughts create our reality so try not to think about the unfortunate incident and instead try to think about something pleasant!! When we think about an unpleasant past incident, it colors our present with negative emotions. Briefly acknowledge that that past incident made you feel bad then get into the habit of thinking or doing something that make you feel good. It takes time to train your mind to do this but you can learn!