We knew that

I don't usually read self-help books or even books about self-help books, which is, in part, what The Happiness Project is. The author, Gretchen Rubin, is a little too self-congratulatory for my Irish genes, which stress not making a big fuss over one's accomplishments.

That said, the book's summary of research on marriage and intimacy perfectly captures the essence of a number of conversations I've had over the years with my women friends:

Perhaps because men have this low standard for what qualifies as intimacy, both men and women find relationships with women to be more intimate and enjoyable than those with men. Women have more feelings of empathy for other people than men do (though women and men have about the same degree of empathy for animals, whatever that means). In fact, for both men and women--and this finding struck me as highly significant--the most reliable predictor of not being lonely is the amount of contact with women. Time spent with men doesn't make a difference.

Or, as a female character in Emily Chenoweth's novel, Hello Goodbye, put it:

"People think you need husbands to grow old with, but that's not true--what you really need is that one perfect friend. You can get fat and ornery and grow bunions together."