Apparently the source added: “Denise claimed to Brandi that she was in an open marriage, but she wasn’t and this has hurt Denise’s husband Aaron very much.”
The actress married Aaron in September 2018 after almost a year of dating.
Her Instagram account is filled with pictures of the pair, the most recent on December 1.
The new series of RHOBH is sure to follow the fall out of the clash.
Season 10 of the show is believed to feature Lisa Rinna, Kyle Richards, Teddi Mellencamp, Dorit Kemsley, Erika Jayne and newcomers Garcelle Beauvais and Sutton Stracke.
Express.co.uk has contacted a spokesperson for Denise Richards and Brandi Glanville asking for comment.