Yep 80,000 miles or 8 years, whatever comes first. (From page 18 of your warranty manual)
I would be contacting the regional rep though and seeing if they can do anything for you as a good will gesture under the circumstances. Do you use Top Tier gas or the cheapest you can find when you need to fill up?
If I had to buy a new one it wouldn't be an OEM one.
Federal Emission Control System
Warranty
Federal Warranty Coverage
•Car or Light Duty Truck with a Gross Vehicle
Weight Rating (GVWR) of 8,500 lbs. or less
− 2 years or 24,000 miles and 8 years or
80,000 miles for the catalytic converter or vehicle,
powertrain, control module, whichever comes first.