Katy Perry, Russell Brand Credit: Chris Weeks/WireImage, Gary Gershoff/WireImage

Three months ago, Katy Perry sought revenge on her ex-husband, Russell Brand, when she channeled her anger in a new bitter ditty "Part of Me," but these days, Perry is singing a different tune.

"Katy's been trying to get him back!" a close Perry pal tells Us Weekly of the eight-time Grammy nominee, 27. "She's a lost soul right now."

What led to the singer's change of heart? A solo trip to India April 3 -- the same place where she wed Brand, 36, in 2010. "She'd already been missing Russell," an insider explains. "Being back there stirred up even more old feelings."

Perry may pine for her ex, but a friend of the singer tells Us a reconciliation with the British comic -- who had a series of flings in the wake of filing for divorce December 30 -- is a long shot.

"Right now, Katy and Russell are trying to get to the point where they can at least be friends," says a Perry pal.