A stalker, unknown to Kym, has been targeting the Coronation Street star for at least seven years.
In an emotional interview with The Sun On Sunday, Kym says the troubled individual has stolen her identity - but the police are powerless to help.
Kym, who admits she's scared in her own home and afraid for her three kids, says the impersonator discovered where she lives, posted pictures of her house online, and set up social media profiles in her and her kids' names.
Thirty-nine-year-old Kym, who plays Michelle Connor in the ITV soap, says: "Ever since I found out I've been quite freaked out.
"It's really scary to think there is someone out there pretending to be me and my children, and who could be dangerous."
Kym was also shocked to get flowers from a man tricked into thinking he had been chatting to her on Facebook since 2008.
She went to police but was told there was nothing they could do as she was not in immediate danger.
She continues: "You don't know who they are, what their motivation is, or how far they might go.
"It is frightening being at home thinking, 'Who the hell is this trying to take over my life? Are they outside right now?'
"I was shocked when I was told trying to take over my life wasn't a crime. I really think the law should be changed. I just want this person to stop now before they end up in trouble or do something they regret. It may seem harmless but there's a whole sinister side to it."
Kym is mum to David, 20, Emilie, 17, and Polly, four.
She admits her son began staying at home and would walk her to and from her car to make sure she was okay.
The former Hear'Say singer is now speaking out to warn other parents of the dangers of social media.
Kym is currently dating personal trainer Matt Baker. She split with fiancé Dan Hooper earlier this year.
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