In PEOPLE's exclusive look at Tuesday's episode, Olivia reveals that she has decided to move in with a friend, explaining that she and Ethan have been "struggling" and needed some time away from one other.
"Deciding to move out is the hardest decision I've ever had to make in my relationship with Ethan," she says in a confessional. "I left one night after a really intense argument. And to me, it was just like a survival move and I didn't discuss it beforehand. I didn't know what to do. I think the driving force in me moving out for a time was that I wanted Ethan to be able to make his own decisions and choices, and sometimes I'm really afraid that Ethan goes along with what I say, just because he doesn't want to make me upset. But that's not good for him either."
Olivia, 23, adds: "I felt like if I didn't do something, then we would literally lose our marriage."
But Olivia admits that she doesn't have a long-term plan for how long the separation will last or what their next steps should be.
"I don't know what will happen," she says. "I was trying so hard to, like, make the marriage work. But I just realized that as long as I stayed and kind of kept Ethan's world together, he was able to just ignore everything that was happening."
Becoming emotional, Olivia says that while desperately wants to make their marriage work, she needs to see "change" within the pair's current dynamic.
"Obviously, I love Ethan and I'm willing to wait. But, if I see months and months go by and nothing change, then I think I'll have to, like, face a new reality," she says while holding back tears.
"I'm kind of scared of that," she continues. "I guess I'm kind of in a waiting stage. And the ball's in Ethan's court whether or not we get back together."
Olivia and Ethan, 23, have been married since 2018. Earlier this year, Olivia told fans in an Instagram Story Q&A that the couple was "working through a lot right now" but that "hopefully it will all make us wiser and stronger in the end."
olivia plath/ instagram Olivia and Ethan Plath
Recently, the twosome opened up to PEOPLE about how couples therapy has helped improve their communication.
"If you have two people that don't get each other and have gotten to the point where they're no longer willing to hear the other person, it takes a third person to be the go-between between the two, so that the other person is heard on both ends," Ethan said. "I felt like that was a big thing the therapist helped us with. At the end of the day, it all boils down to communication."
Welcome to Plathville airs Tuesdays (10 p.m. ET) on TLC.