Sadness over a loss is normal, and everyone grieves differently. But some people experience an especially intense kind of mourning. But some people feel consistently upset and preoccupied with the person who has passed away, to the point where their relationships and work suffer for months on end. Such a reaction is known as "complicated grief". The symptoms are unique in their intensity. They include an extreme yearning for the deceased, loneliness, even searching for the deceased in a crowd, and intrusive thoughts about the deceased. Complicated grievers may feel that life has lost its meaning. "They will often say, 'I feel like part of myself died with the person". They aren't in denial, in that they are fully aware that the person is deceased, and yet on a subconscious level, they haven't integrated that information. At some point the two 'realities' butt up against each other—and this may cause them to suffer. 

Studies on treating complicated grief show that it isn't alleviated with depression treatments such as antidepressants, O'Connor says. "That kind of treatment doesn't hit on the patients' yearnings. What is most effective is talk therapy and exposure therapy that helps the person incorporate the death on a deep level. Also, it's helpful to have the patient focus on her future goals, on what she is going to do now that her loved one is gone. (Mary-Frances O'Connor, an assistant professor in psychiatry and biobehavioral sciences at UCLA's medical center)