Did not see this coming! What would you do?

Our parents have been friends for over 30 years. My parents are her (the bride) Godparents and her parents are my sister's Godparents. We knew each other since we took our first breaths (although I was born a couple of months before her). Our extended family even went to childhood events and just recently, her extended family went to my father's surpise party. When we were little, we introduced each other at our birthday parties as each other's cousins. We're family. We call each other's parents "Aunt" and "Uncle" since we could talk. Even though I moved away about 600 miles, we still keep in contact constantly (much thanks to phone calls and social media) and when we see each other, it's like nothing changed.
She is getting married in over a year and already has her dress picked out and venue. I was asked to be one in TWELVE bridesmaids. She has two Maid of Honors. Her cousin and a really nice girl that she known since they were little kids in school. I'm not angry- I'm hurt. We always said that we would be each other's Maid of Honors growing up. I get that I live far away but I have expereince with party planning and can pull a lot of strings where I used to live as I still go up there, etc. If distance was the main reason, then explain that to me because I feel like this is a kick in the face. She is putting me equivlalent to a couple of girls that she only met three years ago. She was a bridesmaid at their wedding so I guess she feels obligated? I get that being a Maid of Honor has a lot of responbilties but at least give me the option to accept or decline. Even a couple of people who know thus far are shocked by this as there is no apparent reason for it! And I was going to help to some things, too, but now I feel like that would be overstepping my boundaries since that would come under Maid of Honor duties. Since I'm a bridesmaid along with 11 other people, I think that it would be foolish for me to do some things that a Maid of Honor would do since afterall, she has two of them already. My thing is this: It dosen't matter if you have 3 Maid of Honors and 11 bridesmaids or your 2 Maid of Honors and 12 bridesmaids. Either way, it's a lot so was it necessary to do this? She sent me pics of the dress, a video, and all so that I could be "there" too. The wedding is over a year away. I've let things slide as that's what family does but this? I don't want to be a hypocrite and act like everything is okay when it's not. I'm not even overreacting as I'm not the only one who thinks it's wrong either and I'm justified. I can't let this one slide as I was always loyal and honest. What would you do? How can I tell her that I'm blindsided by this and extremley hurt? I usually don't even care about petty stuff like this but this is someone who we call each other sisters. Thank you guys!