So I have to rent a car for work. $200 should cover the rental for the next few days.
Check the blinker fluid.
I'm not kidding. It sounds like you've got a component shorted out and that's what is draining your battery. I had the same symptoms with my ex-wife's Volvo several years ago. I had driven the car to the grocery store, and some kid rear-ended me in the parking lot. I looked the car over and saw no visible damage, so I waved him off and we went about our merry way.
The following winter the car's battery would drain over-night. I would charge it, load-test it, checked the alternator, no issues whatsoever. Same thing the next morning... WTF? Finally I notice one of the break lights was dimmer than the other, and upon taking a closer look I saw that it was about 2/3 full of water, lol. So yeah, check the blinker fluid.