I once worked at a horrible business. The boss was crude, made sexual comments, and called us fucking idiots. But it paid pretty good. Then things got worse and I was being expected to finish projects in 1/2 the time they normally take. The pressure was just unreal. After this went on for about a month, got called into the office and fired.
Found out that a coworker who had been at the company for years went through my desk and found a pay stub. I was making a lot more than her, for the same position, and she went to the boss and threw a fit, demanded a raise, and demanded I be let go. She was an evil person. So the boss promised to get rid of me and he was trying to make me quit with all the unreachable goals and pressure he was demanding of me. When that didn't work, he fired me.
That is when I started having PTSD issues. Just horrible depression and anxiety and flashbacks. I have been on meds every since. I still have nightmares about that job years later.