Katy Perry says her break-up from Russell Brand felt like being "punched in the face and kicked down the stairs".

The 'Roar' hitmaker - who split her from ex-husband in 2011 after he ended their marriage via text - has written about her suicidal thoughts in her new song 'By the Grace of God'.

She told The Sunday Times newspaper's Culture magazine: "I'm not the kind of person who is always like 'What doesn't kill you makes you stronger'.

"I was in bed for about two weeks. I was pretty f***ed, yes. It hurt a lot - I got a good knock.

"What I wanted to call this record at first was 'Adult Reality' because 'Teenage Dream' was 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. So I had to face the reality that things are not always on cloud nine."

The 28-year-old singer lost all sense of self-worth when she split from the comedian and hit a downward spiral.

She added: "Unfortunately, although I had the outward self-identity I didn't have the inner kind, I hadn't built that up.

"My self-worth was in someone else's hands which is never a good idea, because it can be taken from you at any time. And it was, and it was shattered."