Forever, as a concept, has always terrified me. I think it’s the finality of the word—that there’s no end, no second act. It’s especially intimidating in the realm of relationships, which are often only deemed “successful” if they never end. You move in with the presumption that you’ll never move out. You marry with the intention of never being on your own again. You get into bed with someone one night and wake up believing you’re through sleeping alone. For a control freak like me, that permanence is overwhelming.

But when I mentioned this anxiety to Raye and Jerry, who have been together for 55 years, they brushed it off like a piece of lint. Don’t focus on what could have been. Think of all that could be. After seeing each other through countless moves, career changes, childbirths, illnesses, and losses, they say their love isn’t made up of one continuous…