People experience depression in many different ways. It can occur suddenly or gradually, and can vary in severity and symptoms. Some people may be able to do everything they usually do but feel less energy, pleasure or concentration. Others find it difficult to get out of bed, dress, eat and take care of themselves.

There is a range of effective treatments for depression including antidepressant medication. However, if taking medication, it is usually beneficial to combine it with psychological treatment to deal with the underlying problems. Psychotherapy for depression will help to process experiences, emotions, and behaviours that contributed to or in the cause of depression, and through that will help to resolve this difficult state. There is light at the end of the tunnel.

Source: http://www.wikipedia.com