Ran across you again...I’m curious, are you an only child? Your mom sounds like she’s being quite territorial, a problem that probably will continue after the wedding.
Your fiancé should absolutely be part of the planning if he wants to be—this day is more about him than it is your parents. Maybe it’s time to sit down by yourself and outline what YOU, and only you, really want, and then tell both your fiancé and your parents. Value their input, but don’t change your mind on something you really want just to avoid an argument. If your mom knows it’s really coming from you, not your fiancé, hopefully she’ll face up to the fact that this is your wedding, not hers (hopefully).