" This is the vicious cycle. When we feel pain from our physical debility, that pain amplifies our sense of hopelessness; the less hopeful we feel, the fewer endorphins and enkephalins and the more CCK we release. The more pain we experience due to these neurochemicals, the less able we are to feel hope. "

― Jerome Groopman , The Anatomy of Hope: How People Prevail in the Face of Illness