There is a glut of literature (popular and scientific) in the field of hedonics (a fancy word for happiness). I think this is largely positive albeit somewhat skewed part of the dialogue on emotions. The sciences of cognition, human behaviour and neurophysiology all are making huge inroads into our understanding of fundamental human emotions: Happiness and Sadness included.
Although, the popular media remain focussed on the positive spectrum of emotional states (Happiness) Medical people live in a world where BAD news is a daily serving. Demonizing the emotional reactions to bad news is intuitively not an appropriate response. In this insightful and engaging cartoon Courtney Stephens sheds light on the essentialness of SADNESS.