In generaly, there are two types of depression: psychotic and neurotic. Psychotic depression is a very serious condition and can be fatal if patients consider suicide. Psychotic (endogenous) depression is genetically conditioned. On the other hand, neurotic depression is a very common condition and it is usually conditioned by the social environment. Perhaps you are are suffering from neurotic depression since you’ve been feeling down. Depression can be treated many ways: psycho-therapy and prescription medicine are the most conventionally used methods. Low self-esteem can also be symptomatic of not understanding our role in life. You might want to explore conventional AND non-traditional treatment therapies for treating this mental condition. The questions, "Who am I?" and "Why am I here?" have been asked throughout the ages and, some say, are the beginning to newer and higher dimensions of self-awareness. Keep seeking and don't lose hope.