What is the most popular US break up song ever?

The most popular US break up song ever is "I Will Always Love You" by Whitney Houston. Released in 1973 by Dolly Parton, the song was covered by Houston for the 1992 film The Bodyguard. Houston's version of the song became a worldwide hit, topping charts in several countries and selling over 20 million copies worldwide. The song has been certified 29-times platinum in the United States, making it one of the best-selling singles in the country.