I've been at this job over a year and a half.

I started by helping out the supervisors with their work, which turned into me doing their work on top of mine.

I've been doing supervisor duties for months now, its not my job. But everyone is so used to me doing it they come to me and I feel bad saying no not my place.

Well one supervisor is leaving, and the one leaving recommended I take her place. But today one of my coworkers was bragging they offered it to him.
I literally want to scream and rage quit. I've worked so hard and they still won't let me move up. Im just fucking stuck in a shit job that gives shit pay.

Im too busy with school and kids to even look for a new one. It just really sucks. I feel like I do so much for nothing.