^ I think I know what she means by the lining. All my Koobas have had that. The Sloane, which is similar to the Lena, in particular, has additional lining on the bottom.
I'm sorry, I think she's out of of line by her conduct. I'd really stand my ground. She first says it is fake, now says it is defective? Which one is it? If she has the receipt data, she's assured it is good. Plus, you've told her to come here. It sounds like remorse to me. If you want to be a witch, you could nicely tell her that no, you won't take it back b/c it was properly represented and authentic and that if she thinks it is so easy to re-sell a bag on e-bay, why doesn't she list it? I've had to do that before when I got a bag I wasn't thrilled with. What's the big deal?