Last year, when my dad told me that he and my aunt were planning our first extended family vacation in decades, my stomach sank. Not because I didn’t want to see my relatives, but because I knew I’d be the only single person on the trip.

As he listed everyone who’d be staying at the rental house in the Outer Banks, all I heard was one couple after the next: my aunt and uncle, my brother and his girlfriend, my cousin and her husband and their toddler, and my other cousin with his wife and their two dogs.

“You wouldn’t mind sleeping on a bunk bed, would you, Corinne?” My dad asked me, the woman in her 30s who has been perennially unpartnered her…