Subsisting on a diet drawn from one food group isn't healthy or gratifying. Even eating cupcakes 24/7 eventually would get old!

Beyond the profound federal perks, married people make more money; we're healthier, physically and emotionally; we produce happier, more stable and more successful kids; we have more sex than our supposedly swinging single friends; we even live longer.

What do women do when they get together? We sit around and talk! Men, not so much. My theory is that this difference is genetic and dates back to the hunter-gatherer societies, when the men had to be quiet as they hunted, lest they scare away the bison and then everyone starved to death and it was all their fault.

Merely watching a romantic comedy causes relationship satisfaction to plummet. Apparently, the bitter realization that maybe it could happen to us, but it obviously hasn't and it probably never will, makes our lives seem unbearably grim in comparison.

Scientific studies about relationships fascinate me, and I devour them hungrily, especially when they give big, fancy-sounding names to everyday experiences.

If you had asked me when I was 28 and in my wedding dress if I ever thought I would end up in my forties flipping my husband the bird over potato chips, I'd say you were crazy.

One study found that people who smile in childhood photographs are less likely to get a divorce.