Angels are supposed to be humble. "God-fearing" is a compliment around here. Your refusal to grovel got mistaken for pride, then arrogance, then selfishness. Other angels are often quick to report others for this sin (out of a jealousy that they would never admit to feeling), and the ones reported are often quick to be cast out for it.
The afterlife is truly unfair, isn't it? You worked so hard for this self-respect, only to be punished for it. (But don't let that make you lose it.)