In 1986, Ted Kooser, who would later serve as U.S. Poet Laureate from 2004-2006, wrote a one-stanza poem on a postcard and sent it to 50 women friends for Valentine's Day. For more than two decades, he continued this tradition of sending an annual Valentine's Day poem to an ever-increasing circle. (According to NPR, Kooser's mailing list grew to 2,700 in 2007, and printing and mailing the valentines that year cost nearly $1,000.) The collected poems are published in Valentines: poems by Ted Kooser, available at the Library.
The first poem in Kooser's collection begins: "If this comes creased and creased again and soiled/ as if I'd opened it a thousand times/ to see if what I'd written here was right,/ it's all because I looked too long for you/ to put it in your pocket." I encourage anyone who likes poetry to read the entire collection. It's a real treat any day, not just Valentine's.
You can listen to Kooser reading some of his other poems at The Poetry Archive.