The Marriage Trap:

Modern marriage doesn't work for the majority of people. The rate of divorce has roughly doubled since the 1960s. Half of all marriages end in divorce. And as sketchy as poll data can be, a recent Rutgers University poll found that only 38 percent of married couples describe themselves as happy. What's curious, though, is that even though marriage doesn't seem to make Americans very happy, they keep getting married (and remarried). Kipnis' essential question is: Why? Why, in what seems like an age of great social freedom, would anyone willingly consent to a life of constricting monogamy? Why has marriage (which she defines broadly as any long-term monogamous relationship) remained a polestar even as ingrained ideas about race, gender, and sexuality have been overturned?

While I agree that in general, and for most people, marriage is a bad idea, the argument that marriage is specifically the cause of so much unhappiness is simply mistaking the symptom for the disease. In other words, "I wish I wasn't married" = "I wish I wasn't alone."