The Ghost actress has fled to Hawaii to mourn the breakdown of her six-year marriage to the Two and a Half Men star.
Although Moore is pushing herself to "stay strong" throughout the separation, friends of the 49-year-old are said to be concerned about her well-being.
"She's determined to clear Ashton out of her life but she has been crying and crying," a source told the Sunday Mirror.
"Demi is heartbroken but keeps repeating the mantra, 'I have to be strong'. She's in Hawaii to do a bit of soul-searching. We're very worried about her."
Moore, who split with Kutcher over claims that he had an affair, is reportedly planning to "punish" her estranged husband during their impending divorce battle.
> Demi Moore, Ashton Kutcher 'had make-or-break trip before divorce'