It just so happened that the theme for the lesson was interconnectedness. We would spend the time exploring partner poses, designed to build community and interdependence within the class. I told the students that this would be a chance to lighten the load that we'd all been carrying the past few days.
After years of trying for a few seconds at a time and giving up, I finally discovered something that works for me -- listening to music about breathing. By listening to music, my mind focuses on one thing, something relaxing, and I can breathe without the silence doing me in. It's still not easy, but it helps.