After a while—say, seven years—it may occur to you that you haven't made any new friends lately. But you're happy, and you love your wife, and what's the big deal? The big deal is that unless you keep evolving, you're going to get depressed. Taciturn, grumbly, lonely, and slightly overweight: Your new friends will become Mr. Bag of Cheez Doodles, Mr. Gin and Tonic, Mr. Trader Joe's Chocolate Doo-Dads with Sea Salt, and Mr. On Demand. You'll start to resent "her" friends. You'll develop odd hobbies—calligraphy, maybe—and behave more or less like a mushroom. That's why.

 

Getting married is like joining an all-consuming new religion. Imagine if your best friend became a Mormon or a Jain. You'd both want to go out for dinner, prove how it's not such a big difference after all, how the commonality of your friendship and your love of the Mets is bigger than believing God delivered messages to Joseph Smith on gold plates that were buried in the ground. And you will have that dinner, drink a couple of beers. It may not dawn on you until weeks or even months later, but eventually it'll occur to you that you're no longer speaking the same language. You'll be kind of amazed at the stuff your single friends spend their time worrying about—she had no idea how to make a perfect old-fashioned! she asked me for dinner, but I have tickets to see a Journey tribute band!—and you'll struggle to remember what it was like not to be married. And you will think: on balance, not as good.

 

Suddenly sex with your wife will be like sex with someone you don't know. Kissing your wife will literally feel like kissing her in the first moments you ever met, when you were excited to find out that she even existed. There's a real lesson in this. You don't know what's going to happen in marriage, which from the outside would appear to be the absolute most static human state. Because from the inside, marriage is dynamic, challenging, and from one day to the next mixes the high and the low in such a cocktail that half the time you can't tell if you're drunk or hungover