After my marriage collapsed and I lost my baby, my ex-husband married my sister— the same one who was pregnant with his child. On their wedding day, another sister called me and said quietly, “You shouldn’t miss this.”

I stayed home the night my ex-husband married my sister. But when my youngest sister called, laughing so hard she could barely breathe and told me someone had just exposed him mid-toast and drenched the newlyweds in red paint—I knew I couldn’t stay away. My name is Lucy. I’m 32, and until about a year…