Not all depression is caused by psychological problems. It can also be caused by chemical imbalances, which may be genetic or environmental.
See this: http://www.clinical-depression.co.uk/Depression_Information/causes2.htm + http://en.wikipedia.org/wiki/Chemical_imbalance_theory
Anti-depressants increase rate of suicide 670%. Yes 670% Read this (copy it and paste it into your net address line and hit enter). It won't let me paste the url. Search on FDA ending the astrocities. Anti-depressants increase the risk of suicide by six hundres and seventy percent. I took ONE Effexor tablet and if I did not have quite a lot of experience and knowledge I would have slit my throat. Luckily I knew that it was a drug reaction and that I just had to spend maybe 24 hours or so in hell and I never took another one and recovered. Pharmaceutical companies and doctors and the government who pass these drugs have many lives to answer for. Remember this is what they HAVE told us now. The truth would be a lot worse. Use every other kind of therapy but DON'T USE ANTI-DEPRESSANTS.