Her friend has a lot of nerve asking her to sell the tickets when she hasn’t even paid her back for hers. 

There’s nothing worse than making plans with someone who can’t keep them. When I’m making plans with my closest friends, it’s the easiest thing in the world. I text them and ask if they want to do X on Y date at Z time, and they either say yes or no. I don’t have to remind them of the plans in the days leading up to the day; finally, on the day, I confirm with them that we’re still on for tonight, and 99% of the time, they say yes. If they need to cancel the plans, they usually have the decency to do so a couple of days in advance, so I can plan something else for that night. 

Planning a trip or a concert is a bit more stressful than planning a casual hangout on a Tuesday night. You should check your calendar before making any definitive plans that cost a lot of money. Bailing on an expensive get-together makes the whole experience much more stressful for everyone, especially the person paying with their credit card. If you’re the one causing all of the problems with planning, and you don’t even have skin in the game financially, you’re not going to get invited back for the next girls’ trip or to the next Lorde concert. You can’t expect all of your friends to accommodate your chaotic choices.