AITA for refusing to give up my premium seat for my friend who is not paying for the trip?

I have a trip planned with my friend to Japan. We’ve been planning this trip for the last few years and I’m really excited to go. I found an amazing airline that offers free premium tickets if you do a layover in a different country (not a layover, but you fly over the country which is essentially the same thing). This airline is a huge plane so it has extra seats. We can both get premium seats and still get window seats. <br><br>For the layover, Japan is my dream destination, so obviously I’m not taking the layover part, and neither is anyone else on this flight. So basically the flight will take about 10 hours longer, but I get to visit Japan. My flight will take 40 hours all in, while my friend’s flight only takes 25 hours.<br><br>My friend saw the flight I took and said she wants to do that flight as well. She said I’m being selfish for taking the premium seats on that flight when she wanted them too. She said she should get them since I’m not paying for the tickets and she is. I explained that I’m not paying for my tickets because my company is paying for my flights. I explained that the premium seats are smaller, and I’m tiny so they’re perfect for me, but if you’re bigger than average you’ll be unhappy. She said that’s dumb and I need to give up the seats so everyone can have them, but I told her I’m not giving them up because I’m not paying for the tickets and she can just take her own seat. Now she won’t stop berating me and calling me selfish. So I told her I’m not going on the trip with her anymore and told her she can go with someone else. <br><br>She says I’m being an asshole for canceling the trip over this. She says I need to be a good friend and be willing to work out this problem. She says she doesn’t want to go with anyone else, it has to be us.<br><br>So….AITA?