It's a thing some chicks get, and some just don't...
My ex used to hate the car, my current one loves it! (too bad I don't think I like HER that much anymore).
Cleaning the car out really good, washing/waxing/vacuuming (I do mean a well done cleaning, not sloppy), and going for a ride to a cafe for brunch, using some twisty/empty roads help. Make sure there's NO music, roof is off, and the windows are down.
You COULD use the car in case of an "emergancy" (she forgot to pick up nail polish from the mall), and act like you're trashing the car for what she needs (when you're just having some fun drifting around turns).
Ofcourse this is advice from an 18 year old, so WATCH OUT!
BTW, on a different note:
An auto-x is an AWESOME place to meet hot chicks who understand. However watch out, even those who appear alone, (most of them) have their boyfriends who couldn't make it because off a bigger race! :P
Ahmet
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It's all the driver...