I have nothing wise to say to be honest and i know nothing about gestalt therapy, but... If the goal of the therapy is to show your true feelings, then you did a wonderful job. The refusal to rephrase what you said sounds like showing your feelings too, you didn't want to and you didn't. You don't have to do everything what ppl tell you to do, it doesn't really matter if it's t or someone else. Maybe the rephrasing would have been beneficial, i don't know, but i don't see anything wrong that you confronted group t.