Wisdom on the Old UPS Lady and My Epiphany on Prejudice

I have to learn that many people on this Earth are just flawed.  Like it's a pretty narcissistic thing to say, because it makes me seem like I’m perfect, but it's the truth. So many people have massive flaws and I need to stop thinking automatically that I'm one of them. Like I definitely have my moments, but I can't keep blaming myself for the flaws of others.  I have to just learn that it's truly the way the cookie crumbles. When things happen, it just happens.  There's no way to really change or do things differently.  Things could've been done differently and the same thing could've still happened.  People are just crazy. Sadly, life isn't like the animes...Also, a side note, since I'm typing this months in the future, the old lady, at least as of now, I’m okay with her.  I'm definitely standoffish around her since I still remember the situation and it was off-putting and changed my mental model of her, but nothing bad has happened since.  So technically, I’m chill with her now.