Depression can be caused by many psychological, biological, and environmnetal factors.
Some psychological factors are: trauma from childhood, frustration with body/psychological changes, substance abuse, low self esteem, and disruptions in social relationships.
Some biological factors are: being female, a chemical imbalance, physical illness, and drugs.
Some environmental factors are: social isolation, the death of a loved one, lack of a good support system, financial difficulties, and divorce.
It is important to think about what might have caused your depression, because these are the issues you're going to have to deal with to be happy again.
If you have low self esteem, you're going to have to work on building it, because you can't love life if you hate yourself. Try this: www.depressiondodging.com/selfesteembuilding.html
If you have a chemical imbalance you will need medication be get balanced. Learn more about depression medication here: www.depressiondodging.com/depressionmedication.html
If you're socially isolated or have social anxiety you need to get out and around people again. Its hard to be happy when you're alone. Learn how to deal with social anxiety here: www.depressiondodging.socialanxiety.html
For more causes of depression go here: www.depressiondodging.com/causesofdepression.html