"She is having an affair," senior editor Ian Drew told ABCNews.com at the time. "It's not even a joke or speculation or from a shady source."
"Everyone thought she had this perfect marriage, she always had such a perfect reputation," Drew said. "It's just a surprise to everyone."
After the story of their reputed affair broke, Cibrian released the following statement to reporters:
"Other than being friends and two actors who were romantically intertwined in a movie-for-television we filmed last fall, there is no truth to the reporting initiated by Us magazine. It is a fabricated story that is using random snapshots as connective tissue to create a scandalous relationship."
Rimes, married to Sheremet for seven years, responded to the report in a blog post on her Web site. But she left readers with plenty to read into:
"This is a difficult time for me and my loved ones, but I appreciate all your continued support. I would like to assure all of you that this is a place for you to hear things directly from me and as you all know, not everything in our lives is always black and white. Have faith, Le."
The magazine said the couple's affair began March 7 with a romantic lunch at the restaurant Mosun and Club M. in Laguna Beach, Calif. They held hands, laughed and kissed throughout their dinner.
Then on March 14, Rimes was spotted sans wedding ring carrying a copy of the book "For Better or for Worse: Divorce Reconsidered." Later that day, Us Weekly said she'd checked into a $725-a-night suite at the Malibu Beach Inn. An hour later, Cibrian pulled into the parking lot and headed for Rimes' room. They remained inside with a "Do Not Disturb" sign on the door for more than three hours before leaving separately.
Rimes and Cibrian, who has appeared in episodes of "Samantha Who?" and "Ugly Betty," first met on the set of their television drama "Northern Lights," in which she starred as an Alaskan bush pilot who fell for the new detective in town, played by Cibrian. Through the shoot, which included some steamy love scenes, they became close.
The director Mike Robe told Us: "From the moment we rehearsed, LeAnn and Eddie honestly developed a really strong bond and a warm relationship. I could sense a lot of trust that grew between them. Once I yelled 'cut,' they did have a rapport. They became very good friends."
Various media reports say Rimes' marriage has been in trouble for some time, a product of getting married too young. Rimes wed former backup dancer Sheremet when she was 19.
A friend of the couple told People magazine: "Like any marriage, they've had a couple of rough patches. They've gone to therapy. But they did marry very young and when people marry young it's very difficult to maintain a marriage for the long haul."