I understand the struggle with talking in therapy, too. I have been improving (in some sessions, not all of them) but I've spent a great deal of time talking to my T about how hard it is for me to talk (!) .... Yeah. For me, I think a big part of it is the shame. I feel ashamed and my words just refuse to come out. I try to talk and it comes out all jumbled up with lots of starts and stops.
What I've learned is that therapy is HARD. The worst part for me is when I get stuck in a vortex of nothingness and completely spaced out - not knowing what the heck I'm thinking or needing or even who I am in that moment. It's hard for me to be in that state in front of someone with nowhere to hide. I think it's hard for my T too

Have you talked to your T about your feelings related to the disclosures?