I enjoyed this very much. Filling my mind with positive thoughts and gratitude is a key I hope I never lose. It's also something I am very thankful for.
Some of the things I take for granted are sometimes the things some people would consider great privilege. I'm not well off by any means but I'm thankful I'm not homeless or hungry because there are some poor spirits that are in that shape. I for one have been guilty of fixating on the negative in order to "try and compensate" for imaginary lack or insignificant ideas/things, when really, it's simply trivial compared to the abundance I have around me and the trials of others around me. Some things may not be material abundance but a sunset or giving something to someone who has a need can be a source of abundance from joy. The feeling of peace I get when I meditate is something I consider priceless. I'm beyond grateful for that.
If only I can take my focus off of the negative and pan out my mental vision like a camera on a motion picture set and see the big picture then everything becomes clear for me. It really boils down to perspective I think? My perspective is up to me to create, either a negative stance or a positive stance and I've found the positive takes just as much effort as the negative yet it doesn't make me feel like the wrong side of a piece of tissue. I opt for the positive.
You know, some people in townships in Africa have to share restroom facilities among 900 to 1000 people yet they are thankful they have these facilities because it wasn't long ago they didn't even have them. These same people make the best of circumstances most people would find overwhelmingly depressing...and to think there are places and situations worse than this. When I think about that, it really makes that camera eye pan out and give me some perspective. I may have a mental illness but it could be a lot, lot worse. I'm thankful it isn't.
Sorry for the long post but forgiveness and thankfulness are two keys I have found that really set me free. They're priceless in my opinion. It is a scientific fact that bitterness, unforgiveness, anger and other negative emotions release cortisol and other harmful chemicals into our bodies as I'm sure you all know. I don't want any part of that these days. Guess what? I'm thankful for that too!

...and for all the awesome people here on the forums!
Peace and God Bless.