How do you define what is "normal" in life? Is it not normal for people to have periods of their lives (weeks, months, years) where they feel constantly miserable/sad due to a variety of reasons?
It's a fair question. The mathematician Ted Kaczynski proposed depression to be largely a modern construct (emphasis mine):
> Imagine a society that subjects people to conditions that make them terribly unhappy, then gives them the drugs to take away their unhappiness. Science fiction? It is already happening to some extent in our own society. It is well known that the rate of clinical depression had been greatly increasing in recent decades. We believe that this is due to disruption of the power process, as explained in paragraphs 59-76. But even if we are wrong, the increasing rate of depression is certainly the result of SOME conditions that exist in today's society. Instead of removing the conditions that make people depressed, modern society gives them antidepressant drugs. In effect, antidepressants are a means of modifying an individual's internal state in such a way as to enable him to tolerate social conditions that he would otherwise find intolerable. (Yes, we know that depression is often of purely genetic origin. We are referring here to those cases in which environment plays the predominant role.)
>there is evidently a whole class of drugs effecting the CNS which can produce enormous changes in sedation in euphoria in energizing the whole mental process without doing any perceptible harm to the human body...a great deal of control could be used by not through terror, but by making life seem much more enjoyable than it normally does. Enjoyable to the point, where as I said before, Human beings come to love a state of things by which any reasonable and decent human standard they ought not to love and this I think is perfectly possible.
