It reads to me that the impulsive thing you did was merely an attempt to fight back after having to endure harassment and false accusations at the hands of this person. Sometimes when we take this kind of action the person who’s harassing us will stop, but other times it only fuels the fire, makes the person angrier and eager for revenge, especially when he/she may not be mentally well as you indicated may be the case.
My advice is to discuss this with your attorney. In order to competently represent you, your attorney needs to know everything relevant to the case, and the attorney-client privilege ensures that what you disclose to him remains between the two of you only. The truth will set you free!
I wanted to add that since the purpose of this thread is to find ways to get past your fear, I think your attorney can help you. If you are making the impulsive thing you did into something bigger than it actually is, your attorney should be able to put your mind at ease. If you really do have something to fear should news of what you did get out, your attorney should be able to advise you on how best to protect yourself and proceed forward. Since you are unable to share transparently here on this thread but you can behind closed doors with your attorney, he’s in a much better position to give you the right advice to help you get past your fear.