Not envy, but I am a grudgey motherfucker. If I feel wronged, I will hang onto that insult for just about forever. The thing that helps me the most is focusing on other things. Thinking about how so-and-so did me wrong 5 years ago can still get my dander up, but it's much more enjoyable thinking about the diy project I have planned, that TV show I want to watch, or how I'm going to ever find a remote/wfh job so I don't have to put on pants every day. After a while, it subsides. I'm not over my grad school anger yet, but the stuff from high school is gone! Who cares about that mean nun anymore!
The other helpful thing for me is to flip it around. Yes that person was terrible to me, but what did I learn from it. What can you learn from these people (or your response to these people) that will help you get to where you want? Grad school was miserable and my advisor terrible, but heck if I don't know a TON about how to spot crazy bosses, how to pull useful feedback/direction out of someone being crazy at me, and how to work even when I would rather lay down in the road and die. I also know a lot more about my personal weaknesses/hot buttons and how to work with/around them.