It sure sounds like what I experienced as dissociation. And I could "check out" very, very fast. It took a lot of time before I could slow down the process enough to intervene. It does occur to me that when your T said "he wasn't a member of your family" what he may have meant was but he is a member of the "family of Ts," so that may effect his ability to be as objective or non-defensive as he would be otherwise.
I think this is one of those cases where it may be helpful to e-mail that you may have dissociated because you don't have a clear grasp of what was being said, but I don't think I'd discuss further in e-mail--too many chances for missed understanding.