Most readers who have worked at a career can empathize with you. There isn't much that can be done about a supervisor who has his or her heart set against you. There is usually no way to appeal such a judgment, because it's not based on objective proof. We agree, as we read, that accepting the demotion and living with your changed fortune was the only way forward. However, as you describe your acceptance, we feel and share your frustration.

You do a very good job of leading us through the conflict in your office. There is a definite arc in your story. There is a challenge, then temporary good feeling, then deflation. Only later is there satisfaction and resolution.

Thank you for sharing this with us, @zyzymena. One suggestion for future use: in this sentence

It seemed incredulous

You use the word incredulous inappropriately. If you are describing the way you feel about something, then you are incredulous. However, if you are describing something that is unbelievable, that is incredible. We would not note this vocabulary detail in a writer of less sophistication. However, your writing is very good. We like to see your pieces soar.