For is worth is very common between PWS. We are afraid of confrontation. Afraid of the other person getting angry. So there is no surprise that you block. Today I had to change some pants at the store but I lost my receipt. Their policy is that you need the receipt in orden to make the change. I was nervous as hell. I knew I would stutter because of the confrontation. I started thinking the dialogue on my mind when suddenly I step out of my though process and told myself: "Hey, here is again the fear of confrontation. You dont need to practice what you want to say because you already know. You don´t need to see this as confrontation. You are just being assertive in a polite manner. If the other get´s defensive it is his problem not mine" Well the anxiety did not drop off and I stutter like crazy. Hehe just kidding. It did drop off and everything went swell. Anyway.. your history is different because the other person was yelling and angry inmediatly. But the important thing is to acknowledge the fear of confrontation so the next time it arrise you can catch it early on and step out of the loop.