No one fights like brothers. Imagine spending decades with your sibling as a business partner and creative collaborator: there's no place to hide. After a long tour, you look across the table at Thanksgiving and there he is. Have a big fight, and all of a sudden, Mom is on the phone telling you to apologize. It would drive anybody crazy.
The Everly Brothers managed to hold it together during their first 20 years, but things came to a head when Don showed up drunk to a show in Hollywood in 1973. He kept screwing up the lyrics until Phil smashed a guitar over his head and stormed out. The only time the brothers spoke during the next decade was at their father's funeral. The brothers patched things up in 1983 enough to embark on a lucrative nostalgia tour, but tensions remained. They haven't performed together since a brief European tour in 2005.