oh tree.... I am so glad you haven't left us!

I read your original post, as you know and not a single part of me thinks you are a bad person from what happened in your session, honestly! You were triggered and you went into a protective mode, which is understandable hun! As you have said even your therapist was surprised by your reaction - because he also knows that it was not a normal reaction for you, it was a reaction triggered by past pain. I know right now everything about that session feels painful but hopefully at some stage it may turn out to be of some help as it may open up discussion on the past that you need to work through perhaps.
From reading one of your earlier posts in this thread I just want to say again that no one ever makes someone sexually abuse them, you never made anyone do that to you, you have no blame in any of that.

You are a lovely person, so strong, so caring and helpful to others! You are a good person.