Ariana Madix, Tom Sandoval and Raquel Leviss.Photo: Amanda Edwards/Getty; Emma McIntyre/WireImage; Charles Sykes/Bravo/Getty

Ariana MadixdiscoveredTom Sandovalwas cheating on her with fellowVanderpump RulesstarRaquel Levissupon seeing a racy video, according to sources.
News broke on Friday that Sandoval, 39, and Madix, 37,splitbecause the TomTom Bar co-owner allegedly cheated with their costar.
Madix then began scrolling and saw their history of inappropriate texts.
“This is someone she thought she knew; someone she planned to spend the rest of her life with. You can’t even put into words that betrayal,” the source added.
“She was supporting his new single,” a second insider said of Madix being at Sandoval’s show on Wednesday. “She had no idea any of this was happening behind her back.”
Also on Wednesday, on the other side of the country, Leviss made an appearance withScheana ShayonWatch What Happens Live with Andy Cohenwhere she defended her decision to kissTom Schwartz, Sandoval’s best friend and business partner.
“I’m just trying to live my life and I’m sorry if that offends people but it’s not going to stop me from doing what I’m going to do,” Leviss said, later givingAndy Cohena TomTom sweatshirt as a gift.
RELATED VIDEO: ‘Vanderpump Rules’ Stars Tom Sandoval and Ariana Madix Split as Cameras Pick Back Up for Bravo Show
After the taping, Leviss admitted to Shay the truth about her and Sandoval, a third source told PEOPLE.
“Scheana was furious,” the source said. “She and all theVanderpump Rulescostars have rallied around Ariana during this time. They can’t believe Raquel would do something like that.”
A fourth source told PEOPLE earlier on Friday that Madix and Sandoval had been having problems “for a while” but that learning of this “was the final straw for Ariana” after nine years together.
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“She put up with a lot over the years, but she won’t sit back and be disrespected this way,” the insider said.
Madix, Leviss and Sandoval could not be reached for comment, and have not publicly addressed the allegations.
Fans will likelysee the drama play outon season 10 of the Bravo series, which is airing now.
A source close to production told PEOPLE that “cameras are rolling right now.”
source: people.com