The married New Yorker is facing divorce proceedings from her husband Andrew in the wake of sensational allegations she is carrying Cowell's first child.
Reports in the U.S. suggest Silverman is around 10 weeks pregnant, and it has now emerged she broke down and wept when a journalist from the New York Post asked in May (13) if she and The X Factor boss were lovers.
Editors at the publication report mother-of-one Silverman sobbed and told them, "Simon is my best friend, but please don't write we are having an affair... It would destroy my family and my son."
The publication also suggests Cowell's close friendship with Silverman sparked the end of his engagement to make-up artist Mezhgan Hussainy in 2011.