it's always a Jen's fault...
anyhoo... this is what i don't understand. When a girl is obviously way into a guy that just isn't feeling it or just despises the girl, why do guys decide this is the time to spare their feelings instead of just being the assh*le they should be? I have a friend at work going thru a similar situation as you Craig. And I tell him to just be brutally honest and say "hey i don't like you, so leave me alone." but he doesn't want to be a dickhead. That frustrates me when a guy just can't be up front with you.
Right now you are giving this neighbor chick an open door. (no pun intended.) you have tried being nice and explained that you have a gf but she isn't getting it. so... blow her off. she'll get over it. life will go on and you would have saved your relationship with your gf and your neighbor can just be, well, your neighbor.