Mary Cosby Opens Up About Why She Hasn't Spoken to Her Mom in 25 Years

The Real Housewives of Salt Lake City's tubing trip in the October 24 episode started off with some drama as Mary Cosby and Lisa Barlow got into it on the limo ride to the outing. Mary reflects on that conflict with Lisa and the future of their friendship in the above exclusive first look at the next episode of RHOSLC airing on Sunday, October 31 at 9/8c.

In the Bravo Insider clip, Mary gets emotional opening up to Heather Gay and Whitney Rose about what it was that "triggered" her in that moment with Lisa. "Lisa, when you question me, it just triggers. I lost someone over that. Don't question what I'm saying," Mary says. "My mom was my friend. I thought that was my best friend. I thought whatever I chose, she knew that I was capable of handling the right choice. I lost my mom because I knew I was right, and I wasn't backing down. She cut me off."

Mary shares more about her family in an interview in the sneak peek, explaining that the rift with her mom began after the Salt Lake City Housewife was set to wed her late grandmother Rosemary Cosby's second husband, Robert Cosby, to whom Mary has been married for more than 20 years now.

She also explains how her issues with her mom play a role in her tension with Lisa. "When we departed, and I haven't spoke to her in 25 years, it was because she didn't believe what I said," Mary shares of her mother in an interview in the above clip. "So when people question me like Lisa, 'Oh, let me Google what Mary said,' then it takes me back to that wound."

Mary goes on to share with Heather and Whitney "what hurts the most" in her fractured relationship with her mom and whether resolution is at all in sight. She also opens up more about what her siblings, her sister and three brothers, think about Mary's estrangement from their mother.

Want more RHOSLC? New episodes air every Sunday at 9/8c or catch up on the Bravo app.