Kody Brown says he is now living in “total civil war” following his splits from Meri, Christine and Janelle Brown

Kody Brown is adjusting a new normal following the end of his polygamous arrangement with Meri Brown, Christine Brown and Janelle Brown.

On the upcoming season of Sister Wives, the Browns — including Kody’s only remaining wife Robyn Brown — are now “facing new pathways forward.”

“Meri takes her recent decision to leave Kody one step further by appealing to their former church for an official ‘release’ (their version of a divorce),” according to an official synopsis. “Janelle doesn’t need a divorce and is just moving on, which for her means moving away from Flagstaff. Christine has found her soulmate, David. In less than a year, they go on their first date, move in together, and then marry at a beautiful wedding surrounded by family and friends in Moab, Utah.”

“While three of Kody’s wives have left, his fourth wife Robyn remains legally married to him,” the description continues. “Now that the Browns have left polygamy behind, Robyn and Kody face challenges together as a monogamous couple and how to adapt to a lifestyle they never planned on living.”

In addition to the changes in their personal relationship, the family “faces the devastating passing of Janelle and Kody’s son, Garrison Brown. Through the heartbreaking pain, the family navigates this incredible tragedy and comes together to mourn and celebrate his life.”

In the trailer for season 19 of Sister Wives, Meri says she and Kody are “officially done” while Christine reveals she went on a first date with her now-husband David Woolley. Janelle also shares that her relationship with Kody is “not working” anymore.

The splits leave Robyn feeling left in the dust, saying, “This was not the way it was supposed to go.” She later adds, “I feel l like the idiot that got left behind.”

However, Kody wonders where the plural marriage went sideways, asking, “What did I do to deserve this? What did I do wrong?”

Janelle is still concerned about her shared property with Kody and threatens that it may be time to get lawyers involved. “I’ve actually thought about asking if he wants to buy me out, but we got to pay it off, and he’s not talking to me about it, so I think I’m gonna have to lawyer up,” she shares.

Meanwhile, Kody is also facing an uphill battle with Meri, who declares, “I’m not your wife anymore.”

“It’s not divorce that sucks. It’s marrying the wrong person,” Kody says, but Meri counters, “What sucks is marrying the wrong person and not having the decency to tell her until 32 years later.”

Kody realizes that he is now living in a “total civil war.”

The drama shows no signs of slowing down when David meets the Browns and Meri declares that she needs to “find a man.” She adds, “I’m not going to take sides. I’m not going to be in the ex-wives club. I’m not in the Kody and Robyn club.”

Robyn is also having doubts about her relationship with Kody. “I’m having a hard time feeling like I’m losing respect for you,” she says. He then responds, “Robyn, I can’t even get it straight with you right now.”

With his marriages crumbling, Kody makes a last ditch effort with Janelle, telling her, “I keep thinking that you and I could make this work. What about you and me?”

“We have had so many conversations where I said, it’s done, we’re done,” she admits in a confessional. “We’re not compatible.”

The trailer concludes with Meri and Kody having a fight, in which there is no love lost between them.

The original Brown family pair experienced many issues over the years, with Meri’s catfish drama — in which she virtually connected with a woman posing as a male admirer — serving as the tipping point in their strained relationship.

“I wish I wouldn’t have ever married her,” Kody says as he adds how the pair’s relationship was “confusing from day 1.”

“That’s bulls—,” Meri counters. “That is so not fair to me. I would have rather you have told me, Kody, years ago.”

“Blame yourself if I don’t love you,” Kody hits back in a dramatic moment to close the trailer.

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Sister Wives returns Sunday, Sept. 15 at 10 p.m. ET on TLC.