Having both met in Austria while filming for The Jump, Dean Cain is said to have been a shoulder to cry on.
Pictures taken from last week have been published in The Sun showing Rebecca meeting up with Dean, who had flown into London.
The pair were reportedly seen leaving a hotel in central London, having coffee and walking down Oxford Street to shop together.
And now, a source has told the newspaper that the pair "grew close" while filming for The Jump, saying they spent "the whole night chatting away together" at the wrap party.
The newspaper also reported that Rebecca refused to comment about Dean when quizzed by a reporter, telling them: "I just don't want to comment on anything. I know it's just your job, but no, not today."
Reveal have contacted Rebecca and Dean's rep for comment.
Rebecca's outing with Superman star Dean, who is believed to be single, comes after she announced her split from husband Harry on Tuesday (16 March) after just 18 months of marriage.
She said in a statement: "It's after much thought and sadness that we confirm our separation. It is on amicable terms and we still remain close friends. We move forward with respect for one another and our focus and commitment is on parenting our gorgeous daughter Summer. This will be our only comment on this private matter. Becky and Harry."
Rebecca and Harry married in August 2014 and are parents to daughter Summer, who was born in June last year.
Try Reveal's digital edition on iPhone & iPad. Subscribe now & never miss an issue!