Uh... does your girlfriend visit this forum too?... because I saw a thread a little earlier that had seemed like it was your girlfriend asking about the same situation but from her point of view. It was this thread that suddenly is now edited...
http://tfproject.org/tfp/showthread....threadid=23620
Just talk to each other about it... nothing more important in a relationship than communication, and it seems that you two could use some of that right now. You don't want your three times to come back and bite you in the ass in the future... it could definately lead to some problems in her trusting you. Don't just ignore it and let it go because it seems she's really bothered about it.