Michelle's parents send over funds for an upmarket venue later this week. However, things go wrong when she gives the cash to Ciaran to take care of and he ends up losing it to Karl Munro (John Michie) in a poker game.
Ciaran (Keith Duffy) hopes to keep his foolish mistake under wraps in upcoming episodes, but it doesn't take long for Michelle to discover the truth.
Marsh told Take It Easy of the scenes: "She thought that he loved her and he wanted to marry her, but the fact that he's gambled their money makes her feel that she means nothing to him.
"She feels insignificant, like he wants to go off and enjoy himself and have a flighty life and that's not what she wants."
The couple's current storyline sees them realise that they may want different things as Ciaran hopes to return to the cruise ships, while Michelle wants to stay on the street.
Asked how Michelle would choose between Ciaran and the cobbles, Marsh replied: "I know she'd want to go with Ciaran - she adores him and he does love her, but leaving the street, her job and her friends may be a tough choice."
Coronation Street continues tonight at 7.30pm and 8.30pm on ITV1.
> Coronation Street Michelle, Ciaran will stay in love, says Kym Marsh
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