While the Silvermans have been leading separate lives, they are not legally divorced — and Lauren, 36, is reportedly 10 weeks along with "The X Factor" judge's baby.
"Lauren and Andrew have been unhappy in their marriage for some time, and their divorce has been in the works for a while," a source explained to Us magazine. "As their marriage deteriorated, she and Simon became close."
But the two were close even before hooking up publicly, often traveling together — Silverman with her husband and Cowell with his former fiancé, Mezhgan Hussainy.
The foursome traveled to St. Barts together as recently as earlier this year. Here's the pair photographed on vacation together, with their respective significant others, in 2012.
For more photos of the foursome on vacation together, click here >
Now the new couple are reportedly house hunting together in Los Angeles. What a difference a year makes!
When reached by People magazine, an assistant to Cowell's U.K. rep says, "This is a very sensitive issue and all media enquiries are being dealt with by his U.S. attorney." No other calls to reps were returned.
Cowell has been vocal with his fear of
But he apparently changed his tune this year, saying in April, "If I knew I could be – how do I put this delicately – faithful, I would. I do like kids, I’m just not sure I’d be any good for the first six months. I don’t think I’d adopt because I’d rather have my own. I’d have to say I’d like a little girl."
Watch a video of Cowell at a past event sitting next to his ex-fiancé, in black, and Silverman, in blue.