Two things: First, I agree with @Lindagaf writing about trauma is rarely a good idea. One thing I have learned is that people can rarely process something which is traumatic and which they have no experience in dealing with ( this includes murder, rape, car jackings, drug abuse, terrorism etc etc). Sure they can empathize. But they can’t process it. It’s outside the realm of their experience.
Second, no school rejects you personally. They accept the best group of candidates based on who applies. They don’t care that you like their school ( not a factor). They only care about the overall group. And finally, exposure essays raise a lot of questions: 1. Are you going to have issues after the event? 2. Is the person reading it getting a better sense of who you are and what you will bring to their community?
I wish you all the best. I hope that you get the therapy you need. I also hope that you can process the event and heal so that you can have a great college experience.