AITA for trying to get my daughter to dress appropriately for a family event?

My (54F) daughter (30F) came back to our hometown this week to attend her cousin's wedding. She stays at my house whenever she's in town, and a few days ago I went into the guest room to find out what she planned to wear to the wedding. She brought out a dress similar to this, which she was going to wear with ballet flats.

Now the dress was cute enough in its own right. The problem is my daughter is a very big girl and wears a 4XL or 5XL, and while this dress was in her size, it was a bad choice for her shape. She can't wear skirts shorter than ankle length because she has that swollen elephant legs look, and ballet flats only emphasize that even with pantyhose or tights. She also has nothing in the bust area and big creases and dimples in her arms that the sleeves on the dress would accentuate. I've always tried to teach her the importance of dressing for her shape and not to draw attention, but since she moved out on her own she just doesn't care, and it hurts me because I know it's cost her all kinds of opportunities. Nobody wants to see a woman that size in bold colors and showing off their diseased looking legs, it's gross and trashy.

I told her the dress was inappropriate and that she should wear some nice black dress pants instead, since they hide all the lumps and bumps and fat creases, and pair that with a long black or navy blouse like this that won't be too form fitting around the belly. The bigger girls in my office always used to dress that way for work events and they looked very smart and classy.

My daughter tried to argue that I can't tell her what to wear, but in the end I won out and took the dress away. The next day I dropped her off at the plus size store in the local mall and told her to get dress pants and a blouse. After I dropped her off I got about 30 calls and texts from her, all of which I ignored. 4 hours later she came home looking beat to a snot; she'd gotten her father (my ex) to pick her up because she had searched the entire store but found no pants or blouses similar to what I said, worked herself up into a tizzy, and had some kind of meltdown or crying fit. She spent that night and all the next day sick in bed and wound up missing the wedding.

My ex came over today to drop off a wedding favor for her, but she wouldn't come out of the guest room, saying she was busy packing. My ex started scolding me about how the family was asking after her and worried about her (the bride is his niece) and how it was bull that I did this to her. I told him I didn't do a damn thing to her, she did it to herself by not being prepared with anything decent to wear. He continued to accuse me of all kinds of ugly things until I ordered him to leave. I tried to ask my daughter if she feels the same way as her father, but all she said was she's busy getting ready for her trip back and we'll talk later.

AITA?