How do I choose thee, Valentine's Day card? Let me count the ways.

Let's face it: If love is a battlefield, then choosing the right Valentine's Day card for your sweetheart is a minefield. And no wonder: Stress and valentines go way back. The first-ever valentine was reportedly sent in 1415 by Charles I, Duke of Orleans, to his wife while he was imprisoned in the Tower of London. During the American Revolution, battle-hardened soldiers popularized the practice of sending valentines to loved ones.