If you ever find yourself between two married people who are in the middle of an argument, the best strategy is to become suddenly interested in your shoes. 

Married people, of course, know this instinctively. But unmarried people like me have a hard time remembering it. We often imagine that the two married people who are arguing in front of us are having a perfectly ordinary disagreement about whatever it is they’re talking about — the difference between rigatoni pasta and penne pasta, maybe, or if June is a good month for travel — when in fact the source of the discord is something hidden and deeply embedded in their relationship. They are not arguing about what they’re arguing about. They’re arguing about who is more unhinged and which one threw his or her life away for this.