
I might be missing context but it doesn’t seem like she’s keeping the dress she’s just wearing it for the day? Seems reasonable to want a piece of your mom on your wedding day even if the dress looks better on you. And you can still wear it it after this. I think it’ll be sad twenty years from now that you didn’t go, to the wedding. Her wearing the dress might be something you can come to terms with
I get it but it’s your sister. Sometimes you gotta compromise, it’s her wedding it’s her special moment and ik that dress has special meaning to you but it’s your sister in end not like a friend or smth. It’s the same thing as giving your chicken nuggets to your sibling when we were kids. hope you get what I’m saying!