Why is my mother so partial to my sister that she has to punish me for everything? Every time my sister threatens me, she will let my mother beat me and scold me. Why are people so biased?

Go out to find a job after graduation. If you don't want to be with her, go to other places and look for a job. God never shuts one door but he opens another, so why send it to your door to be bullied? I really can't figure out what your mother thinks. I think parents all over the world love their children very much. Not so eccentric. Stand firm outside, be filial. After all, it's your mother. You're on your own in the future.