Some great examples of reasoning with a JW is here:
http://www.jwinfoline.com/page_phone_transcript_main.htm
I just found this site two days ago when searching for some info on 1 Cor 15:50. Yet it looks like everyone and their brother has known about this site for ages. Where have I been?
It is a Jesus/Trinity site though ... but at the very least it is a good site to use to prove to your girlfriend that JWs (at the VERY least) do not REALLY follow the bible.
-ithinkisee