I'm curious, did the facilitator KNOW any of what you brought to the group? IMO they wouldn't have paired you with trivial complainers. Maybe they, also, had big issues but couldn't bear to mention them? I think, once again, that it's the responsibility of the person who's running the group, to guide it so it's beneficial for all participants.

Yes, while some people have a knack, it takes skills that you learn to consistently guide a group well.