Mariah Carey is reportedly blaming Scientology for her split from fiancee James Packer.

The 46-year-old singer was left ''heartbroken'' when her engagement to the Australian billionaire was suddenly called off and she is said to believe that the controversial church has something to do with it.

Insiders claim she feels James - who was a Scientologist between 2002 and 2006 - has been influenced by his business manager and former Church of Scientology spokesperson Tommy Davis, who has poisoned his mind against her.

A source told the NY Post newspaper: ''Mariah and James were looking at homes in Beverly Hills to buy together in August, everything was fine, he was saying she was his soulmate, and he couldn't wait to marry her. Then suddenly he changed. In September, James suddenly seemed not like himself at all. Mariah is suspicious of Tommy, who has been managing James' finances, and she suspects he is controlling him.''

They claimed that James seemed a completely different person when Mariah joined him on his yacht in Greece in September.

The source continued: ''Mariah's manager Stella [Bulochnikov] clashed with Tommy, and she demanded to know what was going on. James was acting so strange that Mariah asked him directly, 'What is going on, are you back in Scientology?' Then she was told by his staff, 'James isn't well and he doesn't want you to see him like this, so please leave.'

''Mariah was stunned. To see the man you are going to marry change overnight. It was like he was a different person. She became very concerned and didn't know how to deal with his sudden change of heart. It is heartbreaking for her.''

However, James' camp have denied Scientology has anything to do with their split and instead blamed it on Mariah's excessive spending and the drama surrounding her as she films a reality show