Sounds like you are starting to feel really attached to your t. You said something about trusting her as much as anyone. Maybe... You let her in more than anybody else too... And because you are trusting her so much... You are freaking out.

Happens to me too.

When the attention system is active mentalization goes out the window. I crumble from within. Feels like it anyway. Does this remind you of your relationship with anyone from your past? Who was the last person you really cared about and let in? What happened with that? How about before that? How about before that? What is your recurrent pattern of interaction?

Maybe you are starting to play it out with your t.

Congradulations.
Progress.

Hang in there...