Compared to when you first started seeing your new T, you've seem to have made a lot of progress in the relationship (least imo from what I've read).

I think you're still grieving the loss of your other T. She was safe and familiar. Maybe, deep down, you're holding yourself back? Fear of another loss? I know that's why I didn't want to be attached to my T.

Maybe you can take a little time to get to know new T better? Find something you can relate more with her about.