Running into the person that fired you
I've been fired a few times before I got it right and found a job I could handle and I worked there long enough to retire. Getting fired is not fun I can tell you that. I have never run into a former employer but I often wonder what I would do if I did.
Two people I know did run into the person that fired them. My ex-wife was at a shopping center when she ran into her ex-boss. He had terminated her for not being able to handle the job. My wife just stood there looking upset. Then she ran to me and explained who the woman was. She was in a panic to get away from the store.
I personally thought that all she had to do was ignore the person and if the person said something respond in kind.
My first cousin was fired from the city job he had had for five years. It was his fault but I won't get into that. His former manager went to the same church he did and he changed churches.
If I ran into a former employer I would say nothing and ignore the person and if they said something to me whether it was good, bad or mediocre I would tell them to get f***** and I don't care who was with them.