There are so many things we are in charge of in our life. Our mindset and our actions are thee most important. For example, If someone didn’t treat you fairly, you are not responsible for holding onto the anger they caused. You are only accountable for your own actions and that’s it.
I’ve seen so many people’s behaviors be heavily influenced by what others did not do ... “this person did not clean up, so I won’t either”. “that person did not say hi, so I won’t say hi either “. “They did not treat me with respect, so I won’t treat them with respect either”. “No fair, they did not have to do that to be successful, why should I do it?”.
Stop allowing pettiness to weigh you down. Don’t allow what other people to keep you from doing what you want or need to do. At the end of the day, ONLY YOU are responsible for the things YOU do - NO ONE ELSE.