moh dress dilemma

I first choose the color/style of dress based off of the weather climate and city (this is a destination wedding which I have never been to). We chose Cartagena in Colombia thinking "let's be adventurous and have fun". Little did I know what I was getting myself into. Since then, MOH tried to put her two cents on choosing the "right dress material and color" by going on an online shopping spree (just to show me how dark colors look amazing on her) AND by sending other friends talk to me and try to change my mind. Only because she wanted to wear dark colors like black or burgundy instead of champagne. Months go by and we unfortunately encountered issues with our wedding planner attempting to play us (I guess this is common for foreign travelers) which a lawyer had to be hired and involved, we fired her along with all the vendor we initially hired from her. Moving forward, we hired a new wedding planner along with all new vendors, last minute changes happened all over the place (including changing the wedding date and venue for ceremony and reception) along with the stupid color of the girls dresses and price (I decided tog o for an almond color dress which was listed for $300). Of course the only person I hear this being an issue is from the MOH. Unfortunately, I hear it from mutual friends rather than herself. Complaining that "I couldn't make up my mind" and "I am controlling" and this was affecting her so much (mind you she makes around $180 hourly) and the first dress she bought was less than $100. I take full responsibility here for all last minute changes, obviously this affects everybody else but us the bride and groom. Not to mention I absolutely volunteered to refund that money for the dress which she declined. But for some reason it wasn't enough. Of course she kept saying "I will wear whatever you want" and gave me the silent treatment for months. I kept hearing bullshit from other people instead of her. I don't know what her problem is. I confronted her in a very nice way and upfront apologized for any and all inconvenience and stress I caused and she is absolutely welcome to wear the first initial dress which she already bought and that it would be nice if she comes to me about any issues moving forward. Nothing has affected me more emotionally than her stupid tantrum over a dress... really? I am at a point of stress where I had to resign my full time job because all of this was triggering migraines, all while doing full time school and moving into a new house. I really just want to drop everything. I have come to a point where I have 0 positive association with this wedding. So much money is being thrown, and we are so close (120 days left) I don't know what to do. She doesn't feel like a friend to me at all anymore. Dilemma is, she's my fiancé's best friend (the best man). Should I fire her?