Am i overreacting to my Moh’s behavior?

This will be long, but it’s for context.


My MOH was someone I grew up with and was close to. We haven’t been as close in recent years and she no longer lives where I do, but we still had a relationship and talked/texted. There wasn’t anyone else I could imagine being my MOH. She agreed to be, and seemed excited the first couple of weeks. That was nearly eight months ago. Now, we planned to pay for attire, hair and makeup, jewelry and even help with hotel rooms the night before (out of town wedding, though it’s close to my former MOH) for our wedding party, because my FH and I didn’t want to financially burden them for our day. I also didn’t want a shower and didn’t expect them to plan a bachelorette, I was just going to suggest she and I and my bridesmaid get together for dinner and girl talk when we got to that point. I did ask my girls for their opinions on the dress and hair and makeup looks, but my MOH told me she would wear/look however I wanted her to as it was my wedding, so literally the only thing I needed her to do was try on the dress because through someone else trying it on I realized it ran small. For months (I chose the dress in February) I asked and we would make plans and she would bail every time, often not even letting me know until I called to confirm plans before I drove to her, and she never set up a new day to meet until I prodded her to do so. Each time seemed like a valid reason, but it was every single time. She never made an effort to try the dress on by herself either. I didn’t want to hurt the relationship and I know she has her own life with stuff going on, I listened to her vent about plenty of it during all of this and I know she had a lot on her plate for some of this time, so I had been letting it go, but that dress has to be ordered by month’s end so it’s crunch time. After another failed attempt yesterday, I finally had enough and told her that I was tired of her bailing on me and I couldn’t understand why she couldn’t make time to do this one thing for me. I made sure to be to the point and not rude about it, even though I was ticked off. She almost immediately says she should step down then, and wouldn’t even discuss it with me. I was fine with her stepping down, I was ready to ask her to anyway, but I felt like we needed to talk for the sake of our friendship. Apparently she didn’t, and I didn’t hear from her after that.
I just feel very hurt that I asked so little and yet she wasn’t willing to do that for me, it’s hard for me to feel like she cares at all about our relationship. It’s making me question if I should even still invite her to the wedding. My FH and I recently decided to have a smaller, more intimate wedding, so we’re talking 25 people including the wedding party, not like she’ll be one person in a group of 100 I will barely see if I don’t want to. Part of me thinks I should invite her so as to not risk severing things entirely, but with the way I feel about all of this, I kind of don’t want her there. Am I overreacting and being unreasonable? I don’t think I am, but I see threads all the time about stuff like this and the comments are usually tearing the bride to shreds saying everyone has their own lives and the brides expect too much. I wasn’t expecting much so I don’t think that’s the case here, but I’m also in it so maybe I see it differently. Should I just invite her?