The pair went public as a couple at New Year and seemed to be building up a stable relationship, but it won't be smooth sailing for them over the next few weeks.
Viewers will see Moira reject Cain after he is finally honest with her about his feelings in an upcoming episode.
Hordley told TV Times: "They're like two teenagers who can't admit their feelings for each other. She keeps urging him to open up, and then when he does, she doesn't want to know."
In the aftermath of the split, Moira starts pursuing other men on nights out with new friend Vanessa Woodfield.
Robb explained: "Moira doesn't try to hurt Cain deliberately. She just doesn't like the way that everything has to turn into a fight with him. She doesn't want that kind of violence around her family."
However, the pair have been tipped to reunite in the long-run as Cain needs Moira's support when his daughter Debbie continues to involve herself in criminal activity.
Hordley said: "Debbie goes off the rails, making Cain become an adult. He craves a bit of stability.
"They're a good match. [Moira] has fire in her belly - that's the attraction for Cain. Thanks to Moira, we're going to see a different side to him."
Emmerdale airs an hour-long episode tonight (January 22) from 7pm on ITV.
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