I hope it goes well. Keep in mind it could take him a bit of time to process everything. Even if he doesn't react in the way you hope he will at first, he may just need a bit of time. It's likely to be something you'll need to discuss more in future sessions. My current T seemed a bit weird the first time I talked to him about attachment (even though he knew all about my intense attachment to ex-MC, since that was a big part of why I started seeing him). But I think he just needed more time to understand, to comprehend why I was experiencing it and what was going on with me, to figure out what I wanted and needed from him and what he was willing to give (which was ultimately more than I'd expected). From what he's said, he hasn't had much experience with attached clients (or at least ones sharing their attachment with him). And even though he seems to be handling it quite well now, I still get shaky and scared when I talk to him about it, like yesterday when I was talking about the stone he'd lent me as a transitional object and how holding it helped me deal with a stressful situation. It's a scary topic.

I hope your T comes through for you and responds well. I sincerely doubt he'd just terminate you, but it may take him time to process. Take the benzo (maybe split it in half?) if you think it will help. And I wonder if it might be more helpful to leave the room for a few minutes while he's reading it--not sure what his office setup is, but is that a possibility? Good luck!