Ah, i just know it is attention! I have acted same way once in RL at school, but did that friend actually care from me? No in hell, she just used me sometimes and had little chat rarely and when her best friend came to same school, i was totally aside. Okay, so when i got to be her pair in school work, i did nearly nothing. That was just my little revenge on it and i enjoyed pissing her off. XD Once she nearly shouted at me in school yard and left even more pissed while i was only watching her and had been staying calm through her yelling. Since that getting of from that school, we never saw each other again (not even via msn cause i blocked her right away after some insulting of hers), but i hear things, she has become more fat
Ofcourse, it's better to block than have little boring small talks or tell her that you don't miss her. "I don't know if i want another boring chit chat" or "If you have hurted me like this, you should just walk away from this instead of stupid small talk" or something else which could work out to make her walk away.