I agree with mrs767er...buddy passes can be more than you think sometimes. Most airlines price them based on milage between cities flown and then are required by US tax law to add normal taxes which may appear to me more than usual because some taxes are built into traditional fares and they aren't on buddy passes. I looked up what the same trip would have been on DL and it would have been as follows:

DAY-EWR-SLC-EWR-DAY
FARE BASIS: BUDDY/Adult
Base USD 160.93
Taxes USD 42.07
TOTAL USD 203.00

Looks like you saved 3 bucks by going CO!!