The actress, who moved to New York with six-year-old daughter Suri after breaking up with Tom, is missing the comfort of being in a stable relationship.
"The exhilaration she felt when she moved out has long since evaporated and Katie is beginning to worry that the grass isn't greener on the other side," a friend tells Reveal.
At the time, Tom's Scientology beliefs were thought to be one of the reasons Katie left. But now, it's been rumoured that Tom is prepared to distance himself from the religion to be with her.
Another source adds: "Tom is no longer volunteering to be the public poster boy for Scientology."
Find out exactly what's going on in this issue of Reveal, which is on sale now!
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