Wedding drama!!

So I'm getting married on Christmas eve. I've still got another year of school so basically all the dresses have to be ordered by September and all the planning must be done so I can focus on school. So I've got my dress picked out. It's a very traditional and elegant dress. I'm getting married in a church in the afternoon. So I want my bridesmaids wearing short dresses. I've picked the dress and all my bridesmaids like it except one. She is refusing to wear it because it's pink, short and doesn't show enough cleavage. 
Now it's common knowledge that I love pink. People would be shocked if my wedding colours weren't pink. So I don't know why she's fussing when she's known all along. I don't want long dresses because I personally don't like them for bridesmaids (excuse me for wanting to stand out on my day). And I picked a dress with a high neckline because my maid of honour has a scar on her cheast she likes to cover (which all my bridesmaids know). I also don't want a bunch of cleavage because it's a church wedding. She also won't wear heels- only cowboy boots. Now I love cowboy boots but just not at my wedding. I just don't know how to deal with this. I've said (and done) that is wear and do whatever the bride wanted even if I hated her choices. Because it's her day! 
I don't know what else to do! I don't want to cut her from the wedding but I feel like I have to. I'm even paying for the dress and shoes!