Oh, I'm so sorry you are having this difficulty. I had that happen to where individual therapy suddenly became group. Have you been in a group at all before? That too can be difficult.

What I found helpful was having individual and group therapy together but with different therapists (all of whom I knew; I had a male and a female group therapists, they were not related to one another, just long-time coworkers and then I had a different individual therapist).

I hope you get more comfortable in group and get to know some of the others there a bit better so it is not so scary.