Songfacts®:

• This ethereal song finds Perry recalling her failed marriage with Russell Brand. "We were best friends... now, you're just a ghost," she croons over synth stabs. Perry penned the tune with Bonnie McKee, Henry Walter, Max Martin and Dr. Luke. The same team also wrote the Prism tracks "Roar," "Legendary Lovers" and "Birthday."
• The lyric, "You sent a text. It's like the wind changed your mind," references how Russell Brand coldly delivered the news he wanted a divorce.
• This is one of several tracks on Prism that were inspired by the breakdown of Perry's marriage to Russell Brand. When asked by the UK newspaper The Sunday Times how their breakup inspired her new album, the singer replied: "What I wanted to call this record at first was Adult Reality. Teenage Dream was me so high on that cotton-candy cloud, and then it's like I got punched in the face and kicked down the stairs a couple of times."
  
  "I had to face the reality that things are not always on cloud nine," she added. "I was down and out, I'd lost hope, all of my self-confidence had been shattered."