sorter

I booked a single room at a resort where a family event is happening, as I am single without a traveling companion. This resort is all-inclusive, and it doesn't matter what kind of room you book. It is the same price across the board. They charge by the person not by the room. My cousin, who I am close with, called to book a room and apparently there was only a room that sleeps 6 people left so she booked thay room. She is bringing her boyfriend on the trip. She invited her brother (also my cousin), and he has decided to come on the trip. We are not sure if there are enough rooms to accommodate him getting his own room. She asked me if I would be willing to switch her rooms and share a room with her brother so that her and her boyfriend could have my single room. I told her that I was sure the resort could accommodate her brother having his own room and that I think it would be nice if we could all have our own space, instead of having to share rooms. She acted upset that I wouldn't switch rooms, as if I was being selfish. AITA?