Kym Marsh's split from fiancé Dan Hooper was due to his "meddling" ex-girlfriend.
The couple were set to marry later this year after celebrating their one-year anniversary, but reportedly decided to take a break because of a series of arguments about Dan's ex, 'Hollyoaks' actress Stephanie Waring, with whom he has two-year-old daughter Lexi Grace.
A source said: "Stephanie just won't leave Dan and Kym alone. She is constantly calling Dan and has been meddling in their relationship.
"Her behaviour has worn them both down, and had a really negative impact. No one wants to deal with hassle like this from their ex."
Although the 38-year-old 'Coronation Street' star is not "jealous" of the fellow actress, - who Dan dated for five years - a source close to the pair claims Stephanie has been "a major problem".
The source told The Sun newspaper: "Kym and Dan have always struggled over dealing with the issue of Stephanie.
"Dan and Steph were together for five years and still see each other because of their daughter. Dan doesn't have the option of shutting her out.
"He would never go back with Steph and Kym knows that. Trust has never been an issue and Kym has never been jealous of Steph.
"But tensions have built up between Dan and Kym, and that lead to a massive argument over the weekend.
"The Steph situation is not the sole cause of the split but it has been a major problem."
However, an upset Dan, 32, took to Twitter yesterday (12.05.15) to insist the couple have not broken up but are merely spending some time away from each other.
He wrote: "Nothing's broken off. We are having space and a break. False headlines. Please leave us alone with the horrible comments. (sic)"
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