Love Is Blind's Dave Discusses That Shocking Bombshell in Aftermath of His Split from Lauren: 'Psychotic Behavior' (Exclusive) liennhi

Warning: this story contains spoilers from Love Is Blind season 8.

David "Dave" Bettenberg has learned more since his Love Is Blind breakup with Lauren O'Brien.

The former fiancés split prior to the season 8 finale after it was revealed that Lauren, 31, had been seeing another man before the show — and Dave's inner circle happened to know the guy.

As a result, Dave started to question Lauren's intentions and whether she was truly ready for marriage. She insisted things were not serious between them and begged Dave to let her explain herself to his friends and family, but he never gave her the chance. After failing to see eye-to-eye on the matter and Dave subsequently questioning why Lauren's father didn't want to be featured on the show, the pair called things off in episode 11.

But, during the season 8 reunion on Sunday, March 9, Dave confirmed that the man had allegedly been "planting this idea" in his friends' and sister's head, "knowing it would get back to me." He added that his mindset "has completely shifted ... since the truth of this guy came to light."

Speaking to PEOPLE about exactly what he learned, Dave, 33, says, "It was all fabricated and he did it on purpose because he's trying to manipulate his way into the show."

"Honestly, it's embarrassing and it's desperate for attention and it's pathetic," he says. "Watching what he's doing right now is just pathetic. Me and Lauren have talked. We're like, we don't even want to talk about this guy and give him the attention that he wants. Because he's been literally planning this for a year. Plotting and planning this behind the scenes, and flat-out lying to people that know me specifically so I would hear about it. That's literally psychotic behavior. That's not okay."

Because Dave only learned this information a few weeks ago, he said at the reunion that he regrets the way things ended with Lauren and considers her the "one that got away." In his conversation with PEOPLE, he echoed those sentiments.

"Throughout this entire past year, I still thought what I initially thought was the truth, and now I just feel like an idiot," he admits. "I've apologized to Lauren so many times. I believed the people that he was telling all this stuff to, and I didn't know what else to do. There's no real right answer to how to navigate that."

"I have this entirely different perspective and the way I'm seeing things," he adds. "Because in that moment, when me and Lauren eventually don't work out, and it's mostly because of this guy, I'm just making the best judgment call I can in that time with the information that I have from people that I trust... There was no way I was going to spin that in her favor unfortunately at the time."

Dave also wonders what could've been, had this not happened.

"Now me and Lauren, we're joking around with each other and texting back and forth how much we hate this guy and how disappointing it is that people feel the need to do stuff like this," he says. "But he did it at the expense of our relationship. What if we would've worked out had he not done that? He is ruining people's futures and lives."

"You could never have expected what happened to us. That was just so bizarre," he adds.

Despite everything, Dave is hopeful about a possible reconciliation with Lauren — even if she previously told PEOPLE that "there's not a path forward for us in terms of a romantic relationship" because "that ship has sailed."

"Man, it's possible... we'll see," he says. "I'm still kind of processing all this new information and just trying to understand why anybody would do that, and it's just messed up. But maybe — I'm not going to say no, I'm not going to say yes."

"I think once all this blows over the next few months or so, I'm sure me and Lauren, if we're both single, talk about it and see if there's some connection there," he adds. "Because I mean, I definitely still have feelings for her. I don't know how she feels, but yeah."

Love Is Blind season 8 can be streamed in full on Netflix.