Just answer the questions honestly:

What was wrong with your old car?: Nothing.
Why did you buy that?: 'Cause I wanted it.
You must have too much money: Yes

Really, most women (not all) just don't get the car thing. Their view on a car is usually concentrated on if it can get them form one mall to the next, how many cupholders for bottled water does it have, and how large is the "makeup" mirror. Engine sound, road feel, handling, etc. are all a mute point.