" But the fatigue of physical dysfunction, I came to recognize, is as different from normal sleep deprivation as COVID-19 is from the common cold. It was not caused by needing sleep, I thought, but by my body’s cellular conviction that it needed to conserve energy in order to fix whatever was wrong. The feeling erased my will, the sense of identity that drives most of us. The worst part of my fatigue was the loss of an intact sense of self. "
― Meghan O'Rourke , The Invisible Kingdom: Reimagining Chronic Illness