This one happens during the engagement party, not the wedding, but they called off the engagement because of it so it still counts as a "wedding disaster" in our book. Katherine Heigl's bridezilla sister gives her a pre-written toast with instructions not to change a single word. Heigl decides to supplement it with a slideshow exposing her sister's promiscuity, hatred of dogs and babies, and ... love of ribs? Sure, she lied to her fiance about being a vegetarian, but still, was the rib-shaming really necessary? It's the 21st century, Katherine Heigl.Â
Special mention: the bride turns into a literal bridezilla in Monsters vs. Aliens.Â