I can relate to this. 3 and a half years and my defenses are still up for most of the time. When we approach something sensitive, I usually try to laugh it off. It frustrated me and we recently talked about it again and what it is that I am afraid of. I know it's not my T, I'm like that in general, I'm usually quiet and don't really show many emotions, although I can feel them inside. I think people think that I just don't care. It's really hard for me to bring those walls down, I've never cried there and after all this time I don't think I will, and it's ok, it's not something I can force, but I have felt emotions in session and he knows when I'm sad. But normally I just go really quiet and don't really look at my T, once when it was really intense I just curled up in the corner of the couch and we didn't say anything for few minutes. Interestingly at time when I do manage to bring the walls down and somehow express myself, I completely shut down in the next session.

Not sure I can be much of help, I'm starting to realize that it's a long process for some of us and it's a little step at a time.