Reusing Center Stone from Prior Engagement Ring?

I had an engagement ring from a prior (failed engagement). My new fiancee knew I had the ring and I tried, unsuccessfully to sell it. When I bought the new ring I used the center stone from the old one in a new setting. The stone was approximately 1.1 ct. and high quality. The new setting was also nice and from a designer jeweler. I did this to save money for a better honeymoon or towards a future house down payment. I didn't tell her about the stone but she found out and is very upset. Was I wrong to do this?