"This song in particular is a dose of reality," Perry told Calloway in a video posted to MTV's site Monday. "It's kind of like coming down from a high. You've been on cloud nine for so long, and it can't always be so sweet and sometimes you need to realize that, and you have to pick yourself up and move forward and face the facts of life and know that this is just a lesson you learn and you're stronger because of it."
"Wide Awake" is not the first of Perry's songs to seemingly reference Brand, whom she divorced in February after 14 months of marriage. With its mentions of diamond rings and packed bags, Perry's last single, "Part of Me," also seemed to be about her split -- though the singer claimed she wrote the song two years earlier.
Perry isn't the first musician to release a track with semi-autobiographical, split-inspired lyrics. Click below for seven other songs that tackle real-life breakups.