Group settings ARE difficult. And yes, do protect yourself as much as you need to within that group setting. If they force you to talk, that's not comfortable, and I wouldn't want that myself. But if you are free to share when you feel like it, and if you are free to share as much or as little as you feel like sharing, that makes it a much safer environment.

I had a graduate program that was much like group therapy. We were forced to share our feelings every day, which I resented and hated. And if we shared deeper stories about ourselves, the professors were sometimes not careful about our emotions and triggers. So my advice would be to only open up when you feel safe to do so... if they are supportive like you say, then they will be nurturing.