Ok, here's a follow up to the story about my coworker and her very expensive Honda Accord.
Some of the comments on the previous post suggested that she was an idiot and that she deserved being saddled with this loan for being so bad with money. That's a bit harsh, but understandable based on the information I shared. As for the math, yeah the extra cost was mostly various charges related to breaking the lease (along with the purchase price of the car being more than the $10k that I remembered). She realizes that she should never have cancelled the lease, and has received plenty of shit about it from other less tactful coworkers.
Here's the upsetting new information I got. Her boyfriend didn't go with her to the dealership, but was on the phone for some of it until the batteries died. To his credit, the last thing he said before the batteries died was "get out of there." According to her, she was crying in the finance office, and trying to back out of the deal when the sales guy came in and they both pressured her into signing. At this point, her boyfriend had already told her to leave and not deal with them, so she definitely screwed up by not walking, but not everyone thinks straight in high pressure situations like that.
In the end, she knows she screwed up, and it wasn't really a problem of math, but a problem of intimidation and not standing her ground (or walking away). Pretty big price to pay, and one she'll be paying for a few more years.