Be thankful that:
- There is a choice (whether it's GTFO, work for another, or just not work anymore, whatever- you have the power. You're not helpless)
- You know "the truth" by now (so what you do with it is up to you- Again, you have the power)
- You are your own master. How you react to screwups in general, doesn't matter if it's your screwups or not, is entirely up to you. Nobody can ultimately affect you mentally except you