Jack and I joined two other couples for a weekend in Asheville, to celebrate the end of 2016 (which has been a real mixed bag for all of us) and the wine-and-laughter-soaked start of 2017 with its blank calendar squares of hope.

It is fun to watch three couples interact with others while being their two-unit selves. You have the individual; you have the couple; and you have the team. Sometimes the difference between any of these borders is blurry; at other times they can be uncomfortably non-opaque.

One person forgot essential meds; another dropped a bag that held a bottle of hard-to-get wine, shattering it and soaking some rather delicate Christmas gifts in alcohol – sadly, not an improvement in this case. Spouses tend to be harder on internal errors than anyone else, yet protective of those who make them. It is okay for one of two to say “you idiot,” but not anyone else. Not that anyone else would, you know, because what makes us exhausted inside couples is no big deal outside. It’s all new; it’s all good.

There’s a quote about marriage that says partners are like the blades in scissors, always moving separately and even in different directions, yet always working together and quite capable of punishing anything that comes between them. I think of that quote often watching sets of two:one interact with larger numbers.

Perhaps it’s like reversing those long algebra equations where you’re meant to prioritize the relationships inside the brackets first; fail that, and your mathematical answer will be wrong. But in human interaction, outside the brackets we add up grace, empathy, and laughing first, so that the sum of the parts becomes simple and fun and gestalt. Inside the brackets where the math can be tighter and more complex, maybe you’re tired of talking it over, had it with being the spouse who looks after things. But as you walk down the street in your big group of giggling friends, your spouse reaches for your hand, or tuck yours into the crook of his arm, and the rest dissolves. It’s all right.

Because marriages, like friendship weekends at New Year’s, celebrate not just the hopes to come, but the good and bad past memories that shaped the brackets you live in and made you the happy two:one you are.