Sunday's episode kicked off with the longtime couple arguing over Kody's continuous demand for "loyalty" from Janelle. Janelle, Kody's second wife, was particularly frustrated by Kody constantly putting fourth wife Robyn Brown on a pedestal.
As the discussion shifted toward the current state of their marriage, Janelle and Kody, both 53, admitted they were concerned about where things might be heading.
"You and I've been acting like we weren't a married couple for most of our marriage, Janelle," said Kody. "I don't know why it's been OK for so many years, and it's not now, but you actually live like a single woman."
In her defense, Janelle said she believed her independence was what "plural marriage is about."
"I enjoy the independence," she continued. "I don't know how it got started, but I've enjoyed it. I feel like somehow, maybe we lost something."
Janelle Brown/Instagram; Gabe Ginsberg/FilmMagic
Kody then questioned whether their relationship "is not a good fit," asking, "Maybe this doesn't work?"
Janelle brought up how she felt the "rules have changed" in their marriage, which had left her uncertain as to how to navigate their shifting dynamic as partners.
"I never thought that I would ever be in a place where I would be questioning my relationship, but the last few years, I began to wonder if we're compatible anymore," she later said in an interview. "Maybe this doesn't work anymore for me. I don't know."
Kody then shared in a separate interview that he had been "evaluating" his life.
Referencing his split from former third wife Christine Brown, he wondered, "Are we going to be any better than me and Christine if we don't improve something here? That's what I'm looking for."
tlc Kody Brown and Janelle Brown
Back in his conversation with Janelle, Kody confessed, "For me, emotionally, it's sinking. The ship is sinking."
Janelle then told the cameras, "I don't know if you can change the way our relationship was for 30 years all the sudden I mean, maybe that's a sign that it just doesn't work anymore." She added she was starting to realize she couldn't give him all that he needs.
After questioning in a confessional whether this marriage was "working" for them any longer, Kody said there was "something fundamentally wrong" with their relationship. Janelle, in turn, suggested that the pair do a "reset."
"I just feel like I have to do everything I can to make this work. I'm not even sure it's possible to come back from where we are," she said in a confessional. "I still have so much affection for Kody. I don't know if it's love."
RELATED VIDEO: Sister Wives' Kody Brown Says His Marriage to Janelle Is Strained Over Her RV Living Situation
Separately, Kody admitted that he needed Janelle to be a "strong enough woman" to help him through his "heartbreak" following his divorce from Christine.
Kody then told Janelle he wanted them to behave like a "married couple" and for Janelle to be "a life partner" to him — but this confused Janelle, who thought they were already doing that.
"I know I don't want to really give up my independence, but I do need to consider you more," she acknowledged, adding that she still wanted to "stay" in their plural marriage.
"We can work this stuff out but, you know, we are going through this transition where I think we are going to have to work it out," said Kody as Janelle responded, "I think you and I are at a very logical place where the kids are now leaving, and also I'm looking at you and I'm like, 'Oh, wow. I think we could have a better relationship.'"
Later in the episode, Kody reflected on his recent sit-down discussion with Janelle that had occurred before he tested positive for COVID.
"At [the] Fat Olives [restaurant], I was having this conversation with Janelle 'cause I was basically begging her to have a deeper relationship with me because I feel so rejected by her," he said in a confessional.
"That got me thoughtful about how I'm not dealing well — or, I'm not dealing with Christine leaving, with her taking Truely," he continued. "I'm experiencing grief because we will never go there again."
RELATED VIDEO: Sister Wives' Christine Brown Wouldn't Wish Her Relationship with Kody 'on Any Friend of Mine'
Kody then recalled looking at old family photos while he was sick. The memory reduced him to tears thinking about how he's going to "lose" the life he'd known He then questioned if social distancing, which caused a lot of turmoil in the family, was even "worth it."
"I've got a division with my family," he said. "I've got a divorce that happened, which, no doubt in my mind, COVID was a catalyst for that."
He added, "It just seems like the family is going in different directions. And it's actually very sad."
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Sister Wives airs Sundays at 10 p.m. ET on TLC.