Hmmmmmmmm... this is the way I feel about my neighbor that my roommate's are friends with.. I just ignore her. Don't even acknoledge she exists. She says, "Hi", I just keep watching the tv. If I'm talking to my roommates and she makes a comment, I continue the conversation without even stopping to see if she said anything interesting. I won't answer the phone when she calls, I won't answer the door when she knocks.
Of course, everytime I'm around and she says something stupid I'll remember it and chalk about another mark in the "How many ways to I hate this person column." When she's over (6 out of 7 nights), I just go to my room and read the forums.