Although I think there is minor, life depression (which people just need to suck up and move on.) However some people really do have chemical imbalances in their brains that make them depressed for no apparent reason.
I'm not a biochemist. I think that stuff about chemical imbalances sells a lot more prescription drugs than addressing psychological distress.
People who kill themselves hate living more than they hate the idea of dying. Dying is actually a better deal to them than living. That is how fucking miserable they are.
Our perception of reality is our own psychological experience. For sure, people can have messed up brains, but every case of depression I have seen or experienced had to do with unresolved issues, which leads to lower self-esteem, which leads to withdrawal socially, which leads to all sorts of other lifestyle collapses which increasingly isolate people, and reinforce the depression.
I get the nihilism shit. I really do. Try being an anarchist, understanding the farce that is most people's political and social beliefs. Try understanding what a joke religion is. Try talking to most "normal people" and realizing you might as well be speaking to a tree or a rock, with the depth of understanding their even capable of, let alone interested in.
But at the end of the day, we're here, and this is how reality is.
The only thing left for us is to deal with it or change it.
If things are revoltingly the same, accept that or change it.
But enough moping. Seriously. This forum is filled with brilliant people who are capable of changing the world in all sorts of ways I can't even imagine.
Life isn't meaningless, it's our fucking canvas.
Make art. Be art.