I never experienced something like this, but I think that what you should do is attempt to deal with it in other ways... Perhaps you could try to rant to other sources like maybe an external counselor, or some sort of person who will understand you better. I do understand how it feels like to deal with trauma, though.. and it's really horrible.
But the fact remains that this trauma or whatever caused it... is kinda already in the past. The sooner you let go of it and attempt to move on, the better.
I'm sorry I that I can't answer your question, but I can promise you that I'll be here if you want someone to rant to or talk to about.
Perhaps you could talk to your pastoral care manager and let him know that there's a lot of pressure on you, and that you don't want your parents to know too much at the moment. In return, promise him that you'll be safe.
Hoping for more moments that will make you smile and be happy.