YANBU to be upset, you can't help your emotions.
YWBBU to ruin her celebrations by voicing this opinion at the moment though. I know when i got engaged, one friend who I was bridesmaid for in the past was upset hadn't done everything i could- brought her dirnks, dinner, sent her a letter- to 'soften the blow' of not being a bridesmaid. I'd only been upfront and honest that I would have love to but was on a tight budget and had to have my younger family members so could have few adults. A few hours after she found out, face to face with me at lunch, she rang me up and gave me an ear bashing, making me feel guilty and accusing me of loving her less and not returning the 'favor'.
Truth was and is I closer to my best friends, which she knew before hand anyway.These friends are close to me, they've been there for me. I was surprised she asked me because while we're good friends we aren't really close, often she seems happy to get me off the phone asap when i call her for a chat-and this was prior to the engagement. Also i had to have, for family diplomacy, my two nieces and sister and given the shit my sister had been through having something else to focus on made her very happy.
My friend completely ruined my happy 'i can't believe i'm actually engaged moment', she made it all about her and basically told me she felt i owed her for the dress she brought me, she made it all about her standing up there in the Bridesmaid dresses. She didn't want to support me or be there for me, she just wanted me to buy her a nice dress while my other adult bridesmaids actually want to be there for me as a friend, person and when it comes to getting married.
I haven't and doubt i will ever forgive her for ruining that time for me. I felt sick, ill, like a bad friend and barely slept.
I would never expect my bridesmaids to ask me back, nor do i expect anyone else to. You don't give to receive, you give because you want to share with your nearest and dearest. I know that it hurts sometimes when you aren't nearest and dearest but you have to be a bit practical sometimes-if i had all my close friends I'd have 9 more Bridesmaids.
Apparently being part of the Bridal party wasn't enough for my friend also, I had asked said friend to do a reading for me but this was a 'cop out' because 'she wanted the dress'. Sometimes, sadly, it's all about people wanting to e that center of attention.
I'm not saying you're like that OP, but your last line makes me wonder I have to admit. Like my friend you feel you are owed and seem to want to punish her for not 'paying up'. If she wouldn't make a good GM don't make her one but it is petty as i'm sure others have told you. Your emotions aren't, your last line is.