So is the media going to pick up on this or not? Too inflammatory? What is going on. The guy accused his coach of showing up to team activities under the influence. Where is the media covereage of this?
Next time the conversation turns in that direction, you should emphatically reassure her that you love her body and no matter how it changes with age, you will continue to love her. That is a part of growing old together. You could throw in a joke about your balls sagging and ask if they bother her smacking the back of her knees when you have sex.
However, confidence is the key to success in life. Confidence before competence. If having impressive cleavage would do anything to boost her confidence, it is money well spent. I would tell her you have saved money for a rainy day and would do anything to make her happy. You wouldn't mind skipping the trip to Vegas that you had planned in order for her to be happy. Again, making it her decision and NOT ABOUT YOU.