But if she doesn't go with you aren't you stuck with an extra seat on the plane that you've already paid for AND you'll have to pay for the room too since that was what she was suppose to pay for?! Am I remembering the original post correctly?
Hope she comes through for you and pays her share. I'd sure re-think ever planning a trip with this person again!
Either way - have fun. Maybe you can win back your excess expenses at the slots or tables.