Am i in the wrong?

Hello everybody, this is my first time ever writing a forum, so I apologize if it's not the best, please bare with me! I will also disclose that this might be a little on the longer side because theres a lot of background!!

My fiance and I got engaged on July 5th, 2019. My cousin and I were best friends and we often discussed having each other as the others maid of honor and even discussed having our significant others ask for the others blessing (much like you do to the brides father). So obviously when my fiance finally popped the question I immediately asked my cousin to be my maid of honor and she happily accepted!
Through the months I would text her every so often about her opinion on certain things pertaining to the wedding. While she would always share her opinion, she would follow up with "But it's your wedding, whatever you want, you get!" Awesome, right?! She even told me that she has to best bachelorette party ever planned for me at a winery, which is 110% my type of party!!Fast forward a few months. In October she received a random Facebook friend request from somebody she didnt know. She accepted the request and asked him who he was. He disclosed that he didnt actually know her but some how they ended up by getting each others phone numbers and texting, I'm uncertain about the specifics. After a few weeks of texting they finally hang out for the first time and hang out a few more times before he officially asks her to be his girlfriend around December. One day she shows us a picture of him and it turns out my fiance knows him because they went to school together. One might think it's a good thing that they know each other, right? Wrong. He was involved with a very bad group of people, engaged in less than desirable actions, was arrested, and even held a loaded gun to my fiance's friends head (this friend is also invited to our wedding). I feel like it is important to disclose now that my fiance and I are both law enforcement. My cousins new boyfriend would always say how nervous he was to meet us because of our jobs (red flag that she ignored).So, my fiance and I discussed it, at length, and decided that we would not like him to be at our wedding, considering his past, our jobs, and the fact that a decent portion of our guest list is law enforcement.I will admit, I took a long time to finally tell my cousin about our decision, because I was trying to figure out the right time and the right way to tell her. Finally, on Januray 7th, the guilt of not telling her yet was just eating me alive, so I decided that it was time. I will admit, my method in telling her was not the best, I did it through text and for that I was wrong, but I simply couldnt keep this from her any longer.I expected her to be upset, I would be too if the tables were turned; however, I expected her to at least understand our decision considering our jobs and the fact that the person he held a gun to is coming to our wedding. As can be expected she freaked out over text, so I let her cool down for a little bit. Then a few hours later that day she texted me "I respect your decision on what you and [your fiance] have to say. Im sorry to say this but it is early enough in the future, im going to have to decline the title of your maid of honor. Im still your family and your friend but I see a complication in the future if I stayed your maid of honor."I received this text as I was leaving work for my hour commute back home. I was heartbroken. I couldnt believe the words I was reading. I read them over and over again, trying to understand how I am misreading them, but that is what she said. As stupid as it sounds, I felt so betrayed. She said she could not be her cousins/best friends maid of honor because I said she could not bring her boyfriend, that she just MET not even 3 months prior, and she picked him over me.I did not answer that text from her and that was the last exchange we have had.Are my fiance and I in the wrong for saying he cant come? Should I apologize to her for some reason? Should I wait for her to apologize? I am still at a loss of words 3.5 months later.