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.

As relationships progress, the time you spend smooching diminishes. Where kissing was once an enjoyable entree unto itself, it becomes a mere appetizer couples hasten through on the way to the main course.

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.

Divorce is contagious. That's right - when you have a close couple friend split up, it increases your chances of getting a divorce by 75 percent.

I don't care how handsome or fabulous or funny the groom is, or how sweet and accommodating the bride, or vice versa. Marriage is hard.

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

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