Hi Mark. I'm sorry it's taken me so long to get this posted. Usually, I get an email to let me know when someone posts, but that didn't happen this time.
It sounds like your girlfriend's bad breath has you stuck between a rock and a hard place. I think the solution is simple even though it might not be easy to do. You need to tell her. You're going to break it off with her anyway if the situation doesn't change, right?
The impression I get from your post is that she's a keeper and that this relationship is worth preserving. So, break it to her gently and compassionately. Start by telling her that you have something to tell her which may hurt her feelings and that you're sorry if it does, but you care about her and feel that it's something she would want to know.
Once you've talked it out, help her get a hold of TheraBreath Oral Rinse and Tooth Gel. She can order through this site or go to most any local pharmacy such as Walgreens or Rite Aid for faster acquisition.
When you discuss the problem with her Mark, make sure you're ready for her response. I'm not talking about how upset she might become. You see, we don't always know how our own breath smells to those around us. It's always possible that she might have similar news for you. ;-)
In the event that things don't go well when you tell her, you'll know that you tried and that one way or the other, it was going to be time to move on.
I hope this helps. Please post back and let me know things go. Good luck!