The closest thing to that would likely be a Sago Cay dessert party at the Grand Floridian. You can definitely wear your wedding dress to that, but there is an additional fee to pipe in the soundtrack.
You could go to the Christmas Party in a non-Wedding dress though. Something pretty, as long as it does not resemble a wedding dress.
When we were there last month, we saw a girl entering MK at night wearing a quinceanera dress.