Is OTHER wrong in the post ? POST : A friend of mine (let's call her "Katie") recently organized a camping trip to celebrate her birthday. Everyone split the cost for food and reserving the campsite, and a few of us (myself included) pitched in extra by bringing tents and other camping gear or driving people to and from the campsite. Most of us also brought a gift for Katie. There were around ten or twelve people on the trip in total, though not everyone stayed for the whole time.

A few days before we were supposed to leave, I realized that one of the other attendees (I'll call her "Elizabeth") was also going to have a birthday during the trip. Elizabeth is one of my oldest friends, but has only been good friend with Katie for a year or so, so I figured that Katie hadn't realized that their birthdays are so close together. Elizabeth is a quiet and modest type, so I doubted she'd speak up about it herself, but I would have felt bad if her birthday went by without anyone acknowledging it. So, I texted Katie to give her a heads-up that Elizabeth's birthday would fall during the trip, and offered to pick up a cake or a card or whatever she thought would be best.

To my surprise, Katie was completely against the idea and told me in no uncertain terms that she did not want to celebrate someone else's birthday during her birthday trip. I reminded her that the whole trip was already dedicated to celebrating her birthday, and it didn't seem like a huge deal to briefly acknowledge Elizabeth's birthday as well. She just kept repeating that it was HER birthday and HER party, and she wasn't going to share it with anyone else. 

I was really upset by that point and almost decided to skip the trip entirely, but ended up going because I'd already paid my share and committed to bringing a couple of tents. I brought a card and a small gift for Elizabeth, which I gave to her privately.

Weirdly, Katie did end up bringing a cake for Elizabeth. My theories for this are: 1) she had a last-minute change of heart, or 2) that was the plan all along, and she wanted to make herself look like the only one who bothered to remember.

I feel like I wasn't out of line here, but I don't know. Is there some rule about this that I didn't know about? Am I the asshole?