My wife secretly had her wedding ring appraised and found out it was a cubic zirconia?

As a result of evil marketing campaigns and subsequent social conventions, it's a fact that all women love diamonds. I'm not a cheap person, but it's insanely stupid to donk off $9,000 of my bankroll just so she can have a shiny rock on her finger and feel validated within her social circle. Well, she had the ring that I gave her appraised and got really upset with me when she found out it was a cubic zirconia LOL. I tried to reason with her, explaining that the money could be spent on more practical things, like maybe a house payment or college tuition for our future children. She maintained her irrational position that I was insulting her by giving her a cheap symbol of unity. How can I convince my wife that, like every other woman, she's been brainwashed (scammed) into this belief that every married woman should sport a diamond ring which sets the family back into serious debt?