chimbly - If she doesn't respond to you, denies things, etc., start up a claim (or whatever you want to call it) process with eBay:

http://pages.ebay.com/help/tp/inr-snad-process.html

It might take a while, but I feel like eBay would probably be on your side for this thing. Be sure to save all those photos from her posting so you can have them to present alongside your own. Not sure what else to suggest. IMO, better to have your money back than an f-ed up bike, even if it was one you really wanted.