i don't know how new you are exactly, but i should warn you there are other options than curses. sometimes they are a good idea, but the majority of the time people don't see [or refuse to see] the other options. as mentioned, a banishing spell would keep them away from you. a stop gossip spell would keep their mouths shut, a protection spell over yourself and your things would decrease the bullying, all of these would not cause harm to them. granted, people want revenge, if thats the case, don't let your anger cloud the right choice.
a spell to reverse the negative energy back at them, or cause the same heartache to befall them would be a good idea. sending some all powerful, year or more curse upon their heads might not be the best solution. you reap what you sew after all, and with magick the energy you send out will come back upon you. perhaps a push to keep them away won't result in you getting hurt, but a giant shove down a flight of stairs could cause yourself to see some bad karma/luck. just reflect and think about it before you do anything.