Do I imply that I'm not done trying, or do I just say "ok" I'll start looking and leave it at that?
Do not imply that you're not done b/c that will cause her to try to prove you wrong.
If she is face to face talking about this, then I would suggest that you simply say, "Okay" and say not one word more about it. If you say anymore than that, she'll be loaded for bear. I don't know how long it will be before the talk, so you may not get this in time. I believe the answer is keeping calm and taking a very light attitude. Why? B/c she isn't expecting that. She's expecting anything but that. After saying "okay", then you could immediately change the subject. May not fly, but so what? Just don't crumble under pressure. Big 180 coming up!
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!
