I feel ur pain a year ago my sis had a sleep over with her friend which I was also included in, and they all ignored me the whole day and night unless I was "apparently" being anoying. But that is worse in your case. In my old school I had to watch multiple ppl get bullied everyday so I stood up for those ppl. Just cuz of that idk y but they didn't harm me as much. It's probably cuz if you show them you don't care about them bullying you, they will just walk away because they want you to suffer, and cry.