“Your absence has gone through me/Like thread through a needle,” poet W. S. Merwin wrote about grief. So how does science advise us to move through it? Dorothy P. Holinger is a psychotherapist and a fellow of the Association of Psychological Science, and she joins host Krys Boyd to talk about the psychological and physiological changes grief causes and the processes that help the bereaved move through it. Her new book is “The Anatomy of Grief.”