The Mamma Mia actress, 31, was thrust into the spotlight after she was spied necking the 50-year-old actor – despite him being very much married and in a “strong” marriage with wife Catherine.
Lily was was booked in for an appearance on the hit NBC show to promote her new Netflix drama Rebecca on Monday.
She stars alongside Armie Hammer, who plays the role of widower Maxim de Winter made famous by Laurence Olivier in Alfred Hitchcock’s Oscar-winning 1940 film version.
But it seems as though she’s not quite ready to face the cameras just yet, as she pulled out at the 11th hour, an insider told PageSix.
Mirror Online has contacted Lily’s reps for comment.
It was just last week when Lily and Dom were pictured passionately kissing during three days sun-soaked in the romantic city.
Dominic – who has been married to Catherine for 10 years and has four children with her – was seen snuggling Lily’s neck and stroking her her over an intimate lunch.
They were also seen hopping onto a scooter together, with Dominic wrapping his arms around Lily, who is his co-star in new TV drama The Pursuit of Love.
Lily is newly-single after splitting from her boyfriend of five years, Matt Smith.
They also hopped on an electric scooter together, with Dom standing close behind Lily and steering the handlebars as she leaned back into him.
He was later seen with his hand on her bum as they went into a picturesque church for some sightseeing.
Dominic has since returned home and he put on a united front with his wife Catherine Fitzgerald – kissing for the cameras and declaring they are still “very much” together.
The married couple were pictured kissing and cuddling outside their Wiltshire home, with the actor declaring the marriage is “still strong”.
However, despite the very public show of unity, friends close to Catherine have claimed to the MailOnline that she is seething about those pictures of her husband.
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