Everyone experiences time of sadness and depression, Particularly after the death of a loved one or the end of a relationship. In most cases, the sadness lasts for a short while, then gradually lifts as the pain of the loss begins to ease. Yet for many, depression doesn't heal with time, but worsens and becomes even more disabling. There is a real difference between being blue and being depressed. Clinical depression tends to linger and worsen with time, and can cause a spiraling effect that touches all areas of a person's life.
Depression directly affects a person's self-esteem, reducing the sense of self worth.
This will often cause depressed people to withdraw from the things they used to enjoy, said Moore. They can isolate themselves from family and friends, and may miss time from work and social activities. Unfortunately, this withdrawal only deepens the depression because it causes more financial and interpersonal problems. The exact nature of depression is unknown, though there is evidence that chemical and biological factors may be partially responsible. Depressed people may lack the coping mechanisms needed to handle such problems.