It's not going to be a fix for everyone, but if you feel like this guy, you should check to see if you've got the rare form of the MTHFR Gene, which means you'll be up to 80% deficient of methylfolate.
Methylfolate is what our body turns folic acid into. It's a base element that our bodies use to function properly. If you've got an extreme deficiency, well, things just aren't functioning properly. People affected with this will have lived with these issues their whole lives.
Now, up to 60% of the population has a mild form of MTHFR, so the gene itself isn't uncommon, it's the rare form you'll be looking for.
Anyway, getting on a high dose of methylfolate changed my life, life from night to day, I'm not kidding. I still take medication for anxiety and depression, but the methylfolate helps them to function like they're supposed to.
Again, it's not a fix for everyone, but on the off chance you have it, I'd check it out.