If you get a reasonable rate of return, investment in your relationship will make it truly better than any other relationship you could have. And that's why I listen to people's vows: to understand what they want out of their marriage or in economist-speak, what they are contracting over.
How important are fidelity, loyalty, generosity, kindness? As an economist I think that a good marriage, like a good employment relationship, has shared vision, common interests, complementary abilities, and gains from specialization.
Read (or listen to) the whole thing.
Betsy Stevenson, by the way, is not married to her long-time beau and fellow cold-hearted economist, Justin Wolfers.
