A marriage may be between two people, but weddings tend to be between the couple and everyone else. Wedding guests called upon to bear witness to the ceremony, and to shower a new couple with verbal and financial blessings, can shape the proceedings and meanings of marital rites as much as the bride and groom do. I’ve played a number of performative roles in the weddings of loved ones — bridesmaid, maid of honor, toast-giver, poetry-reader, choreographer, and stage manager — and from the wings, I’ve observed how often the friends and family of the new couple feel entitled to weigh in on what is and is not done properly. Personally, I lucked out: My own parents’ rules for the ceremonial passage into a hallowed state of matrimony were simple and few.

Rule 1: Don’t get married until you’re 30.

Rule 1b: But you don’t have to get married ever,… More…