<human>: Give me the gist of the text in a nutshell

Both of us live in Iowa but her family lives in Nebraska. I had to work Mother's Day weekend so she went to see her family there. She has not been on a vacation with her family since she was in first grade so this vacation has been something she's been looking forward to for a long time. It was setup by her parents and their church group and the destination is Alaska! Pretty cool since I've never been on a cruise and I've never been to Alaska. We booked a fancy room with a great view, big balcony, and several excursions so this trip has cost me a pretty penny. She spoke about the trip to her parents and talked about how excited she was for the trip. Her mother asked her if we would be married by the time the cruise rolls around (we're eloping later this year) and she said no. She then proceeded to say that I will have to spend the cruise in her brother's room.
 
I only get 10 days of vacation a year and this trip is costing me 7. I'm not spending $2000 so I can go to sleep in a room with her brother. I'm an adult so I'm not used to other people telling me how to spend my free time. What do I do? Do I set an ultimatum or something?
<bot>: Fiance and I are going on alaskan cruise but her parents don't want us sleeping in the same room that I paid for