Tom Sandoval-Raquel Leviss Affair Has Been Going For On AT LEAST 8 Months: Source

"While no-one fully knew it at the time, the first signs that something fishy was happening emerged in July of last year," the source dished of the shocking affair. "Ariana feels completely blindsided by this. She didn’t suspect anything. Others did though."

"This is someone [Ariana] thought she knew; someone she planned to spend the rest of her life with," the source continued. "You can’t even put into words that betrayal."

Sandoval and Madix — who had been dating for nine years prior to their split — have been fan favorites of the Bravo show ever since they joined the program in its very first season back in 2013.

Sandoval and Leviss' fling hit headlines on Friday, March 3, sending rumors swirling about Leviss' recent jaw dropping reveal on the show. Twitter blew up when the TV personality admitted that she liked Sandoval's best pal, Tom Schwartz, to co-stars Katie Maloney and Lala Kent.

Comments under a recent ad for the show questioned whether Madix had been aware of her boyfriend's affair when Leviss made the confession.

As for Sandoval, the musician publicly addressed the cheating scandal at his band's performance at City National Grove in Anaheim, Calif., on Friday night.

"Have you ever been one of the most hated people in America?" the television personality is said to have shouted to the audience in the middle of the show.

A member of the crowd allegedly yelled, "Ariana!" seemingly referencing his affair with Leviss, to which Sandoval called back, "We love her!"

Leviss has yet to comment on the affair.