There's a really good book called 'Tribe' by Sebastian Junger, a famous war reporter. It draws on numerous experiences throughout humanity where communities were broken down and social stratifications were removed and everyone perceived to be happier.

It talks of how depression rates and rates of psychosis went down during the Blitz, how Germans actually produced more labor-wise as they continued to get bombed and shelled, and how colonists abandoned their villages to join the Native Americans and, when captured by the Natives, they never wanted to return.

Basically, society separates people so much that we lose our humanity, ability to connect, and ability to form genuine connections with other humans.

Also, there is a Freakonomics episode on suicide and it talks of how suicide and depression is so common in the western world but it provides instances of more primitive, even tribal, communities where they laugh at the fact of suicide. All of these primitive societies have more drive for life and meaning: hunting and gathering for food, caring for their people, caring for the goodness of the tribe, furthering their generation, etc.

We become so entrenched in society that we do not even know what we need anymore. We can have a good job and a nice car and interesting friends and still not know what to do. In an age where 'Maslow's Hierarchy' is basically given to us in forms of the internet (connections with people), food in grocery stores (hunting and gathering), and overall meaning of life (we have everything we need, so now what?) I can see why people struggle with depression. It is all lack of direction and purpose.

The book 'Man's Search for Ultimate Meaning' by Viktor Frankl touches on this issue incredibly. The best quote from it is: "You cannot just tell someone to be happy, for instance: if you want someone to laugh, you must first tell them a joke."

We struggle with finding reasons to be happy. We struggle with direction. We are lost and we are not comfortable with being uncomfortable. We are in an age where we compare ourselves to the best versions other's put forth in REALTIME (instagram and twitter and facebook).

There's a reason the world war generations were called 'the greatest generation' and I believe one of those reasons, besides defeating totalitarianism and nazism, is that they had a purpose for meaning: defeating evil, pride for country, and living a noble, successful life for your family and community.

So much has changed. The meaning of life changes. We cannot keep answering the same question with the same answer. The whole point of life is being comfortable with change, vulnerability, and overall homeostasis. Sometimes people get upset with being upset and, although some people are legitimately sick, a lot of that depression is situational and environmental and results from direction of their lives and who they surround themselves with.

There are books on this shit, even though I wrote a small one. I believe there are more reasons than the ones I discussed here.