Here we have Mary, who lost her husband. She spent the first month after Rick's death staring at ants marching on the front porch. She kept wondering why insects build a home and a life in places where they know there is danger of being wiped out in the blink of an eye. Why? They do know, don't they? Surely they have learned this lesson and have passed this on to others? Why do they keep doing it? Mary parsed time into "while Rick was here" and "after Rick has gone." It makes sense, to keep on like this. Hopeful.