Just as the body has a physiological immune system, the brain has a psychological immune system. When something goes wrong, we instinctively marshal defense mechanisms. We see silver linings in clouds. We add sugar and water to lemons. We start clinging to clichés. But after losing Dave, I wasn’t able to do any of this. Every time I tried to tell myself things would get better, a louder voice inside my head insisted that they would not.
