I got Shingles because of stress caused by some arbitrary blockage of payments from one of my service providers. I'd say remembering bullshit excuses they gave me was quite difficult.
In the future when you find yourself in this situation, start a paper-trail immediately. Write down the results of communications; keep a folder; etc. If it gets truly ugly and you have been calmly but deliberately and thoroughly taking notes it can be quite intimidating. Think: Mueller investigation of Trump. With all the shit they were throwing at him, he just quietly went about his work in a very methodical, detailed way.
