Katie grew jealous after watching Derek interact and supposedly flirt with Taylor Dunklin, and so she stormed out of a group dinner and accused Derek of not making her feel special or appreciated.
"The way you talk to me and treat me is not any different from how you treat every other girl here," Katie said in the clip. "You don't initiate, like, physically."
Unfiltered host Jamie Otis then asked Katie the following viewer question: "It sometimes seems like you stir up arguments to get Derek to pay you more attention. So did you walk away from Derek because you wanted space or because you wanted him to chase after you?"
"You know what? I think it depends on the situation," Katie replied.
"In this moment, I think he made me so irritated that I was kind of like, 'Okay, I just need to cool down.' But I could also see how in some of our arguments, I might be checking to see if he's going to care enough -- to take that initiative with me."
Although Katie accused Derek of not making moves on her in the bedroom, Derek argued he did in fact initiate intimacy but Katie turned him down because she was menstruating.
When Derek called her out on that, she shouted that married couples still make love on the woman's period, and then she shut down the conversation and walked outside.
Derek naturally chased Katie down, begging her to talk and work things out, but she had no interest in fixing things at the moment.
Also during the Unfiltered episode, Katie vented about how Derek didn't put much effort into their relationship when cameras weren't rolling.
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"I'm still wanting to see more action from him," Katie shared.
"He says the right thing a lot when we are on-camera, which can make him look really good, but it's like as soon as the cameras go away, he doesn't put in that effort and we're not really spending a lot of quality time together."
"We're not having those meaningful conversations that we need to have," she added.
Once Derek apologized and Katie chose to forgive him, the couple bonded over stealing a golf cart and saving a turtle on the side of the road during their drive home.
Katie loved seeing the adventurous, bad-boy side of Derek, and he said he was "turned on" by her playful energy and the fact she was trying to embrace her inner-child.
"I think Katie could be the person that I want to spend the rest of my life with, the person I want to madly love and never look back," Derek said in a confessional in Wednesday night's episode.
"So, I need to figure out how to reassure Katie that she should say, 'Yes,' [on Decision Day]. I want her to say, 'Yes.'"
Katie, however, wasn't sure Derek was the guy for her since they aren't very compatible and had developed more of a friendship than a romance. She seemed torn on whether to stay married come "Decision Day."
"I don't feel special at all... There is a giant emotional disconnect. As soon as I think I'm closing the gap, it shoots way open again," Katie explained to her father Dante.
Katie didn't think Derek knew how to express himself, and she called him "a boy" instead of a man.
Katie had been hoping for an older, more mature man waiting for her at the altar, but she said she got a baby-faced boy with a baby personality to match.