U have to say "enough".....
Tell ur superior u want to pass this job to someone else..... If I'm the boss, I would appreciate that u tell me who has capacity left. Being superior, they also have other things to do. They may not know or noticed who is free, and who isn't.
But should the boss have a negative feel towards ur suggestion, then this boss is not worth working hard for. He is blinded by his own power and may have bad reasons for making u work harder than others.
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