You can be proud of yourself for all you have done already ( drugs, alcohol) and not mad! If your T can't see it that is a shame. You learned coping skills during your trauma that worked for you to protect you. Your therapist diagnosed this and now she expects you what? Drop it after 5 sessions and be all new? She is crazy … she should be helping you to gain trust to learn new healthier coping skills etc. and not expect you to be able to switch something that worked for you all these years off with a snap of your fingers. Not possible !
You sure don't need to feel bad about it or guilty. That is the last thing you need. Maybe next time tell her you need help rather then rejection.
I got quite angry on your behalf and that is something haha. Wish you best of luck on your journey and let's hope your T had bad day and is going to be more patient and understanding in the future.