Yvonne (37) posted a cute snap of herself and John on Twitter with the caption "missing my man tonight".
Yvonne and John seem completely at ease with each other as they beam at the camera in the intimate black and white photo.
The smitten couple have been dating since meeting in Gothenburg in February.
Yvonne was in Sweden chaperoning daughter Missy (11) on the set of horror film Dark Touch when she first caught John's eye.
The loved-up pair have been dating for 10 months and friends close to Yvonne say she is completely besotted with her new man.
A father-of-six, John split from his former wife Suzanne (43) in January. The couple shared a home in Rosenallis in his native Co Laois.
John is a highly regarded cameraman and has been working in the movie industry for over 20 years.
Earlier this year, he worked on the latest series of the BBC's Silent Witness and has also worked on Hollywood blockbusters including Sweeney Todd, The Bourne Ultimatum and The Da Vinci Code.
Last week, Yvonne said she was looking forward to spending a traditional family Christmas with Ronan and the kids at the K Club.
"We're all looking forward to being together on Christmas," she said "Ronan's been busy so it'll be great having him home for Christmas."
But Yvonne said she had "no idea" if Ronan's partner TV producer Storm Uechtritz (30) would be joining them for Christmas dinner.
It is also unclear whether John will spend Christmas day with the Keatings but the Laois man already seems completely at ease with Yvonne's brood, joining the family for lunches and walks around Malahide.
And ex-husband Ronan says he is pleased that Yvonne has found a new man. "I'm delighted," he said. "I'm really happy for her that she's in a great place, and she deserves to be."