You ladies are too nice. I'm sick of these buyers on ebay who don't keep their word. Don't assume that ebay sides with the buyer. Ebay will side with whoever presents their case the best. So far, they have been only receptive to my complaints. Any buyer that threatens you with reporting or bad feedback is jeopardizing her ebay membership. There are lots of rules to protect ebay sellers.
Usually, if a buyer is nice, I will go out of the way to explain things and take things back I don't normally do. If they start with threats and unreasonable demands, they are reported and expelled from ebay.