People need something to believe in. It doesn't have to be a supreme being, but it needs to be some sense of purpose. I was raised atheist and a lot of people assume that because of it, there's no way for me to lead a virtuous life, because they assume I need to fear rotting in hell to avoid temptation. But people do have a moral compass. It's a highly subjective one, of course, which is why people rationalize bad behavior all the time, but we do see things in right and wrong.
The constant fighting on the internet is just that. Anytime someone utters the word "should" they are thinking in terms of right and wrong. Politics and setting policy is all about right and wrong. This usually involves a moral dilemma of some sort. War is the ultimate moral dilemma.
Doomerism raises huge moral dilemmas which we all know about.
So much of the posting here revolves around "shoulds" and "should nots". People point their judgmental finger at one segment of society while giving their own environmental footprint a free-pass. You see this with Planty sermonizing about AGW one moment and bragging about flying from Alaska to Greece the next. The finger just starts pointing around in a big circle of cognitive dissonance.
These dark emotions are about how we bristle at the idea that we've met the enemy and it's us.
That's why there are literally hundreds if not thousands of posts in this forum that go back to 2004 or whenever things started here that rant about one thing or the other. Suburbanites, GW Bush, Obama, the house of Saud, Madison Avenue, the Koch Brothers, on and on and on.... The blame-game.
We've met the enemy and it's us. You can argue on who deserves the most guilt, but it's us, all of us.
The "dark emotions" are therefore mostly about the stages of grief, anger especially.
I keep coming back to this George Harrison clip to keep me going.
https://www.youtube.com/watch?v=RrkQOMsSYaE