Grief often includes physiological distress, separation anxiety, confusion, yearning, obsessive dwelling on the past, and apprehension about the future. Intense grief can become life-threatening through disruption of the immune system, self-neglect, and suicidal thoughts.

Grief may also take the form of regret for something lost, remorse for something done, or sorrow for a mishap to oneself.

Adapted from the APA Dictionary of Psychology"