Sister Wives’ Kody Brown on His ‘Deep State of Mourning’ and ‘Strange’ Transition to Monogamy with Robyn (Exclusive)

“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,” Kody Brown tells PEOPLE

Kody Brown and his wife Robyn are adjusting to a new normal following the collapse of their family.

The 54-year-old Brown family patriarch exclusively tells PEOPLE that he and Robyn becoming a monogamous couple has been “strange” after exes Christine, Janelle and Meri Brown left their plural marriage one by one.

“We’re still in a deep state of mourning, if you will,” the Sister Wives star explains. “We are not recovering from this.”

He adds the pair are “a bit depressed” about what happened to the family, adding, “We’ve been through a very hard experience and our reaction to it has changed us. We are not the same.”

“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, and … you need to let some sunshine back in. That’s the thing,” he adds. “I think we’re just in a transitionary point where I am letting sunshine back in.”

The TLC star says he and his former wives are now in “a different place” as they navigate their own paths to happiness.

“If we are breaking up and we don’t continue seeking happiness and go out and find that happiness, then the breakup was never a benefit,” he shares. “Then you’re living with regret.”

He continues, “But when you first break up, there’s a lot of doubt, especially if you are not the instigator. If you haven’t thought it out enough. If you haven’t been in awareness. I just thought we had killed some trust, and I thought we just needed to build the trust back.”

Kody also reflected on the aftermath of Christine’s decision to walk away from the marriage. “As time progresses and I move out of the anger phase of that experience, I find myself going, ‘Yes, you need your happiness and you weren’t happy,’” he acknowledges. “It was making me unhappy. We go through this terribly unhappy part, and then we move to happiness. If she’s happy, then I’ll be happy. That’s just it.”

He continues, “It’s like there’s doubt and you wonder and you think, ‘Is this right to break up?’ If everybody finds happiness afterwards, then we’ll know that it was just a part of life, just transitioning to a new space.”

In PEOPLE’s exclusive sneak peek at Sunday night’s third installment of the Sister Wives: One on One special, Kody admits he sabotaged himself and his relationship with Robyn “out of frustration and anger” after losing three wives in 14 months.

Telling host Sukanya Krishnan that he wanted to “punish” himself, he adds, “I thought of myself leaving Robyn and having another lover and looking at this lover and going, ‘I don’t love you. I’m in love with another woman. I’m in love with a woman that I left because I was too much a piece of s— to manage the relationship.’ And what it was was just anger and I’m embarrassed.”

He acknowledges that his emotions lead him to have “bad behavior” which ultimately affected his relationship with Robyn, 45.

“These are my demons and that’s like doing something that destroys myself,” he explained. “Christine’s leaving and I’m just angry. So 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.”

Three of Kody’s marriages imploded in less than a year and a half. Christine was the first to leave in November 2021. A year later in December 2022, it was revealed that he had separated from Janelle. Shortly after in January, Meri confirmed that she and Kody had split after their relationship had been platonic and distant for years. Robyn is Kody’s only remaining wife.