Katy Perry is having hypnotherapy to get over John Mayer.

The 'Roar' hitmaker was devastated when her two-year romance to the singer ended in February amid claims he had cheated on her, and she is doing everything she can to move on.

A source said: ''Katy was devastated when they broke up. They had talked about marriage and she seemed to think he was a changed man, so she is beyond gutted.

''But Katy is a firm believer in alternative therapies and she wants to wipe him from her life for good, so she decided to see a hypnotherapist. She wants to retrain her brain to prevent John coming back. She doesn't want to find him attractive anymore.''

The 'Prism' singer - who was previously married to Russell Brand - has split with the 'Gravity' star twice before, but this time she is determined the relationship is over for good.

The source told Britain's Grazia magazine: ''Katy has been really hurt by John and she doesn't want him worming his way back in.

''He hates women moving on from him but this time she's determined to erase him from her life. Her first step was to get him to move all of his belongings out of her home.

''Katy wants a fresh start and she is well on her way to putting her relationship with John firmly in the past.''