Ah, travel New scenery, exciting adventures, time alone with a loved one. Truth is, travel can make or break a relationship. Just negotiating when to leave for the airport can be tricky: she insists on arriving hours ahead of flight time, he likes the excitement of a photo finish. But as Mary-Lou Weisman sees it, "The inevitable rage with which we begin each trip only helps us to better appreciate the good times that lie ahead."

Or maybe not. When people have jet lag, can't speak the language, figure out the money, or maintain intestinal regularity, they get cranky. And since...