Most good providers wouldn't hesitate to give you something for bad breath or to send you to the shower if need be. Why can't you do the same? You may be doing her a favor since she probably can't smell her own breath.

You're the one paying... Some people just have stank breath and they can't really help it though. It's usually caused by certain medications or health problems. Others like me (according to past partners, friends and my own nose) have very neutral breath/no odor and a perfect balance of oral microbes, even if I haven't brushed recently. Drinking plenty of water and eating right definitely helps.

I know, I know - it's a little gross but true. I think you should definitely tell her, because if you smell it then I'm sure other people she sees smells it as well.

halitosis

mouthwash is a two way street..

I can't tell you how many clients of mine have horrible breath even though I leave oral care products in my bathrooms in hopes of them using something while freshening up.  I always keep a listerine strip or breath mint next to the bed  Popping one in and offering one is not a bad idea

It helps to eat garlic .

As long as you know before hand what you are up against , there is usually an adequate remedy .

I'd be prepared for her to be a bit shocked but it would be good to figure something out.   (Acting a bit embarrassed)  "I don't know how to tell you this...  but your breathe...  "   If someone said this to me, I'd be shocked but then it would sink in.   "What can we do to fix this?"  (adjourns to the bathroom for mouthwash...  Then)  "Can we start over???"    

Actually I thank the OP for bringing this up.  I've never had this problem but I have suggested we share a shower...

May be she ate something bef you came or whatever............just send an anonymous email from another account and say that to her she prob isn't aware of it.