Katy Perry is on the cover of the July issue of Vogue - and in the magazine, she opens up about two of her most private relationships: ex-husband Russel Brand and ex-boyfriend John Mayer.

Katy said she hasn't heard from Russell since he sent her a text on New Year's Eve 2011 saying he wanted a divorce.

She says she felt a lot of responsibility for it ending, but then found out the real truth - which she didn't want to talk about. Katy said: "I let go and I was like: This isn't because of me; this is beyond me. So I have moved on from that."

She also opened up about her on-again/off-again relationship with John Mayer.

She says it now over, but she "was madly in love with him".

"All I can say about that relationship is that he's got a beautiful mind. Beautiful mind, tortured soul. I do have to figure out why I am attracted to these broken birds."

"I'm not in a relationship, I'm just on my own — I am myself in my own bed. I have to be happy being alone, and I am happy."

Katy's issue of Vogue will be available on June 25th.