WIBTA if I didn't pay this girl back a cent
A research associate and I are travelling for a conference in less than 48 hours. Costs have been crazy— our hotel was like 1400, my plane ticket like 500, and I'm incredibly grateful that my parents have agreed to bankroll this trip. Splitwise, our hotel would have been around 700 each.
We're both 19, so finding an 18+ hotel in a busy college city was a hassle. It took me 5-6 hours several weeks ago, when a lot of the hotels were already booked out for the conference. It was torture. I finally found one, and it was listed on Expedia for about 1700-1800, I asked her if she was okay with it, she said yes. I later find it on Hopper for about 1400, I texted her, "I'M THE GOAT, 1400," and she, having agreed to 1700 and 1800, agreed happily. After the hotel has been booked, she texts me that night that she can't pay 700 and that she is going to stay with a family friend. After I had already confirmed the hotel. Heart drops. My parents are already freaked out about me travelling alone. I proposed going 60/40 in installments (without a payment plan) with her instead of 50/50 to accommodate her, and also because I want a companion so my parents will let me keep my solo travel plans, which she agreed to immediately. She paid me back in full for her share in the last three weeks.
This morning (48 hours before our check-in!), she texted me that she has "bad news brochacho," and then told me that she is going to stay with that family friend for sure. This came with the expectation to pay her back, which I said I cannot promise, as my parents are under the impression that we are going splitwise on this and don't even know we went 60/40. We agreed to go 50/50 when I bought it, I then let her pay 500 and some change, and I covered the rest.
She then told me that because it is short notice, she is cool with just getting (either 40 or) 60% of her initial, already reduced share back, which puts my personal costs at way over a thousand. I also paid for the registration of the project.
To top it off, she suggested that my girlfriend split the cost because her college is around and she will be visiting, which is just audacious and out of line in my opinion.
I told her I would talk to my parents and keep her posted, but the room is non-refundable at this point, and she broke our agreement twice. All my friends said to give her nothing back, but I need objectivity.
AITA for not wanting to let her sniff the copper of a damn penny?