"You can't say or do anything to take happiness away from me," Mary Cosby said on part two of the reunion

Mary Cosby's marriage may not be conventional, but she says it works for her.

During part two of the Real Housewives of Salt Lake City reunion on Wednesday, Mary became emotional while discussing her unusual marriage to her step-grandfather.

Once again laying out the backstory to her marriage, Mary explained that she wed her late grandmother's second husband, Robert Cosby Sr., in an "arranged" marriage. She said her inheritance was dependent on the union.

"My grandmother told me, for herself, that she wanted me to take her place," she said. "Basically, Robert Sr. was 20 years younger than my grandmother. My grandmother felt like she robbed his youth. So she said, 'If something ever happens, I want you to marry one of my girls, because I know that they will be loyal to you and treat you good like you treated me.'"

Mary Cosby and Robert Cosby Sr. The Real Housewives of Salt Lake City
Credit: Bravo

Once her grandmother died, Mary said she and Robert Sr. "prayed" for the relationship for two years before eventually tying the knot.

"We felt like it was God's will," she added.

Real Housewives of Salt Lake City
Mary Cosby
| Credit: Bravo

Despite the nontraditional start to their relationship, Mary and Robert Sr. have been married for over 20 years and share a teenage son, Robert Jr.

Asked during the reunion if she is "in love" with her husband, Mary replied, "I absolutely think I am."

But when questioned about their physical relationship, Mary said the two have not had sex in the "last few years." She also confirmed that they do not sleep in the same bed and have separate bedrooms.

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Becoming emotional, Mary stressed that while her marriage isn't perfect, she's "happy."

"We're happy," she said, holding back tears. "You can't say or do anything to take happiness away from me. It's hard to get. If you can find that in a man, it doesn't matter where he came from."

"Marriages are hard, they're horrible, they can be a nightmare," she continued. "I have a beautiful one."

The Real Housewives of Salt Lake City reunion will conclude with part three, airing Wednesday at 10 p.m. ET on Bravo.