In my case, my short term trauma was because my sense of self was shattered. I had explanations for why I did a lot of things and suddenly those explanations were replaced by other explanations. My entire view of who I was was thrown into question.

This might not be that traumatic when you're a child - you're still discovering who you are then. However, when you're in your 30's, your sense of who you are is usually set. To have that demolished was hard to deal with, even if it was beneficial in the long term.