I open facebook for 2 minutes a week and scroll through my relatives' baby and pet pictures. I don't get how the site is such a specter of misery for some people Twitter I would understand a little better. It's such a tar pit of negative energy, insults, rage bait, etc
I'm very happy that there are those that can interact with Facebook without negative side effects. If you're in that category, I hope the site adds value to you and you enjoy it. I can't. Yes, it's a failure on me, but my experience is better without Facebook in my life. You mention negativity, and that's part of it. I saw a steady stream of "the world's on fire" type posts. The other side, the rosy view of my friend…
So, the simple reason why fb sucks is that women are in charge of it, it's the gossip corner. And therefore it descends into the angst of pettiness and uselessness, as these are the names of the servants of the superficial.
But the reason why fb is a problem is the fault only of men, wimps who won't give it the one finger salute and delete it.