What broke the cycle for me was realizing it doesn't help thinking about it at all. Eventually when i forced myself not to because I had an inkling that it would get me closer to how I feel at home (I felt like I could say anything at home by myself, to my cat, or what have you, so I had a feeling there was something to it), I did see results and began talking on the phone without a second thought, something that felt impossible for me at times when i dwelled on it endlessly. When you realize the more we dwell on it and worry, the harder, not easier, it gets, you may begin to see it differently and get upset when you start dwelling on it and just think no, and roll your eyes at the thought knowing it's a waste of time. Do you dwell on it at home? On how you will say anything?