we're all entitled to get a little crotchety, esp if our skin is bugging us!Lol
I know you said she's bad in your car, but are there any of those doggy car washes in your area? (OK I just call them that, I know they dont do cars..lol).
We have ones with walk up ramps, the tub is at a good height for the human. Some have the groomer table with noose so you can dry them off without them running around like loonies after the bath.
It might make bath time easier for both of you if you can go to one of those. It's just easier for you to control the dog, and the hand nozzles are very convenient.