The same thing happened to my aunt in 1991, she helped to start a new business that does technical writing and graphics, BUT because she did NOT have a graphics design degree her boss hired a new manager off the street, DESPITE her being with the company from day one for almost 15 years. She took the company to court and won, the owner paid the new manager $50,000 a year while she was only getting $20,000 a year in all that time.

Yup, that's how it goes. When there is a stack of resumes they toss any that are the wrong colour, have misspellings, or where the education just doesn't match what it says in their hiring document.
Now you can stop being such a phenomenal manager, that should be a load off your shoulders.
Meanwhile, find another place to work. Call in sick when you have an interview. Life goes on.