Katy Perry has told how she found strength from writing a song about her split from Russell Brand.
The couple met at the MTV Video Music Awards in September 2009, married a year later and then split after 14 months.
Katy, who has now moved on with new love John Mayer, told Entertainment Weekly the track By The Grace Of God on her new album is about her divorce.
"Well, imagine what you go through," she said. "Imagine what happens when you go through a break up. We all go through break ups and we all get very depressed and desperate. The lyrics are very exact and autobiographical. That's how I write. But the one thing about those lyrics is you can hear me finding my strength throughout the song. It starts off really low and then I kind of stand up for myself and say, 'No!'"
Katy added: "Sometimes you look in the mirror when you're crying and if you look in the mirror it will make you cry more because you're feeling sorry for yourself. And then sometimes you look in the mirror and you cry and I've been like: 'Snap out of it! It's time to - come on - grow up! No!' There's almost like this inner warfare that comes out, this inner battle between the good angel and the bad devil."
But the star insisted that the song - in which she sings about crying on the bathroom floor - is the only track about her break up from Russell.
She said her recent single Unconditionally was partly influenced by current boyfriend John.
"All the other songs are stories from different times in my life," she said. "It's people making assumptions. It's kind of hard because I am so vulnerable and I am [such an] open book, but I don't feel like I want to hand over a specific story about each and every song."