My therapist had an idea once that worked out really well. He asked me to write down things to talk about on slips of paper (I used post it notes) and he would keep them in a container. When we got stuck, he and I would agree to pull one out of the container and discuss them. There's currently only one left in the container and it's something really painful for me to talk about, but he knows it's there and he knows that it's not something I take lightly to talk about. I wonder if something similar would work for you. Your therapist would know that there are things you're having trouble talking about and you could work together to bring them out into the open. I'm actually convinced he knows what that last slip contains but we talk around it. I trust him that he hasn't read it before I've given him permission to read it.