Wow, I can relate very much with the experiences you are describing. Becoming a different person as soon as walking into the theraists office, wanting to share my issues with him but when I'm there I'm just stuck in a state of no thought and escalating anger, becoming this angry child with him and are discussions being around that, me resisting. It just all sounds so familiar...
I don't feel well now, but I want to come back later to this thread and add some more thoughts about this.