If they only want attention then you could approach this two ways. 1) Give them what they want, stand up to them and embarrass the shit out of them in front of everyone. Find out their weaknesses and exploit them. This may not be the best answer to it because it could cause trouble. 2) Act like they don't even exist. Cut them out of your life because they aren't worth it. If they say things to you just simply walk past them and don't say a word. If you show you don't care, they will walk away.