Mary Cosby Calls Son’s Arrest ‘a Blessing in Disguise’ (Exclusive)

Real Housewives of Salt Lake City star Mary Cosby is getting candid about her son Robert Jr.’s recent arrest.

Robert Jr., Mary’s 22-year-old son with husband Robert Sr., was arrested outside of Salt Lake City on Sept. 6, after local police responded to a domestic violence report.

Robert Jr. was accused of attempting to climb through a dog door to break into his father-in-law’s home before allegedly assaulting someone on the front lawn. When police ordered him to get on the ground, Robert Jr. allegedly failed to do so. He ultimately complied before he was arrested.

“It was for his good,” Mary tells PEOPLE. “I think he needed that. He’s never encountered anything like that. He’s never been through anything like that. I don’t mind it. It hurt me at the time. I was devastated, I was worried, I was scared. But some things happen for a reason to show you the path you’re on. I feel like he needed that and that he understands that that’s the wrong journey.”

Robert Jr. tells PEOPLE that he’s taking his journey “day by day” and that he’s “not where I want to be, but I’m certainly not where I used to be.” He adds: “I will get there!”

While Robert Jr.’s wife Alexiana had been living in Mary and Robert Sr.’s home for some time, Mary, 53, says they’d recently “moved her out.”

“She’s out of our house now, so they snuck out to be together and got caught,” Mary claims. “So the parents made sure that he [was arrested for trespassing].”

While Robert Jr. previously revealed that he was married on a 2023 RHOSLC episode, Mary doesn’t believe the marriage is legal.

“I still don’t believe she’s his wife,” she says. “I think they were out of their mind, and they maybe made up something. They said that the marriage license is in a safe, and the safe is locked, and they have to bust it open because they lost the key. They’re toxic together.”

Because they are apart, she says his arrest “became a blessing in disguise.”

Robert Jr. first opened up about his drug addiction in the last season of RHOSLC, and his journey has continued to be shown in the current season 6 of the show. Mary says sharing her son’s struggles with the world has felt “somewhat liberating.”

“It makes me feel like I’m letting the cat out of the bag and freeing myself from holding it in,” she says. “I’m thankful for all the people that have responded to it and appreciated it. Anyone that I can help, I’m here to do so.”

Prior to Robert Jr.’s confession, Mary says she “kept getting DMs” from people telling her about her son’s drug use.

“This one guy was like, ‘He only buys the best and most expensive,'” she recalls. “I was like, ‘What are they talking about?’ After reading these messages, I was trying to put it together, and at first I was just clueless. I just decided to ask him, ‘What is going on?'”

That’s when Robert Jr. confessed on camera to her for the first time that he’d been using drugs like heroin, Xanax, acid, Molly, cocaine and Oxycontin. 

“I think I asked at the right time because we had never talked about it until those cameras were up and rolling,” she says. “We were in his room, and he just was real and honest and he told me the truth and I didn’t judge him. I respected it. I know that talking is the best way to overcome something. When you hide something, you don’t want to change it. I dealt with it in the mindset that if he’s talking about it, it’s because he wants to change.”

Robert Jr. was also open about his mental health struggles, including that he felt like “a stain” in the world.

“In our church, we’ve had a lot of people call and say, ‘Thank you for sharing, because I felt the same way or feel the same way,'” Mary says. “I think the most important part about it is it’s not true. When you go to a place with drugs, you go dark in everything. It’s not the truth. I just feel grateful that he was able to tell me. He’s doing better to this day because of it. It’s brought the best out of him.”

Since that moment, Mary says she and her son have only grown closer.

“The fact that he told me and he admitted it, that is touching,” she says. “It breaks you down, and it makes me love him even more.”

Mary says she’s also let go some of the guilt she’s felt.

“I’ve done a lot of thinking and reflecting and just going over everything that I did,” she says. “I’d think, ‘Maybe if I did this different…’ But then I realize that I can’t change anything. Whatever happened and whatever I did was supposed to happen. I can only control myself, and my kid has to control himself. That’s on him, that’s not on me. The only thing I can do is be supportive, stand back and encourage and beg him to stop. He has to take full accountability for his actions, and he has to want to stop.”

By being so open, Mary is hoping to help others.

“It doesn’t matter who you are. It can reach anybody, and it found us,” she says. “Just watching the news gives me anxiety, so I know why this younger generation is so full of anxiety. The times are different, and they’re very strange and unpredictable. It almost makes you feel like you need something to escape.”

For Mary, she’s found filming RHOSLC to be a form of escape.

“Even with my son going through what he’s going through, I can go and film and just be away and create another section of my life that I can fulfill and be myself and have a good time,” she says. “I don’t get into [the group’s drama]. It’s silly to me. I have bigger problems. I have real ones. I have my own cross that I need to carry before trying to correct someone else.”

As for what fans can expect in the rest of season 6, Mary — who unintentionally became the “comic relief” of the show — says, “this is probably RHOSLC’s best year.”

“This year is so amazing,” she says. “It’s beautiful, it’s captivating, it draws you in, it’s touching. I am proud of all the women. I’m proud of all of us — except Britani [Bateman]. I’m not proud of her. I have no reason to be proud of Britani. Some people are just not your taste.”

The Real Housewives of Salt Lake City airs Tuesdays at 8 p.m. ET on Bravo.