On Sunday’s ‘One on One’ special, Kody confessed to “sabotaging” his relationship with Robyn, emphasizing the “dark winds” that swayed his “destructive” tendencies

Robyn Brown and Kody Brown. Photo: TLC

Sister Wives stars, Robyn and Kody Brown, are still recovering from the way their plural marriage fell apart.

While opening up to PEOPLE about the couple’s transitionary period, Robyn admits that Christine, Janelle and Meri Brown’s departure triggered a “huge upheaval” in Kody’s self-image.

Kody’s marriages to his three sister wives fell apart within 14 months. Though he’s now only married to Robyn, the pair — who wed in 2014 — have experienced many challenges within their relationship following his three splits.

“Kody has been going through a lot and he’s dealt with a lot of frustration and anger and hurt and betrayal, and I’m going through my own emotions about all of it as well,” she explains. “And it’s been hard on our relationship. It’s been really hard on our relationship because I think when you’re going through a divorce, you start questioning yourself.”

The mom of three says that the demise of their plural marriage has also caused Kody to adopt “very self-sabotaging” habits as she noted he has even tried to sabotage their relationship.

“I think he’s just been in such a dark place,” Robyn adds.

Kody also told PEOPLE of the strange “space” the couple have been in since Christine, Janelle and Meri have left.

“Moving forward is still one of those things where you go through a divorce, you almost feel like God doesn’t exist, and you’re so angry, so bitter,” he admits. “You need to let some sunshine back in. That’s the thing. I think we’re just in a transitionary point where I am letting sunshine back in.”

On Sunday’s Sister Wives: One on One special, Robyn told host Sukanya Krishnan exactly how Kody “tries to” sabotage their relationship and how she has to “stop him all the time.”

“He picks fights with me [over] dumb things,” she said through tears. “We’re in different places. We’re in different places about the bomb that went off on our family. And like, I’m in a major place of mourning and he’s angry. He just wants to just go find whatever, you know? And I’m like, ‘No, I can’t feel like that.'”

Admitting to “sabotaging myself a little bit … out of the frustration and anger,” Kody also acknowledged he was purposely hurting his marriage with Robyn because he wanted to “punish” himself. He even considered the possibility of leaving Robyn as a way to further punish himself.

He added, “A lot of dark winds were going through me. A lot of devil, a lot of temptation, which would be destructive of my relationship with Robyn. So I dealt with a lot of anger and she would get frustrated. My anger was a turn-off. It was scary.”

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Sister Wives airs Sundays at 10 p.m. ET on TLC.