Viall, 37, opened up about watching Haibon and Iaconetti’s love story unfold after a complicated three-year friendship.
“I’m very excited for them. They’re both some of my best friends,” he told PEOPLE at the launch of launch of Smirnoff Red, White & Berry in New York City on Wednesday. “I’m very happy for Ashley, obviously, I know she’s kind of always hoped this would happen, and to my surprise, I did not think it would.”
The couple first met three summers ago on Bachelor in Paradise and while it was love at first sight of Iaconetti, Haibon wasn’t convinced they were meant to be. Despite any heartbreak, the two remained friends over the years.
“I think Jared just kind of realized just how special Ashley is to him,” said Viall. “I feel like sometimes, as men, we maybe take too long to figure things out, but I’m glad Jared did. They’re very much in love. Almost to the point of it being slightly obnoxious — but in an adorable way.”
So what made Haibon realize he wanted to be more than friends with Iaconetti? Viall said it was hard for the Bachelorette alum to watch Iaconetti in another relationship.
“I could tell every time Kevin’s name came up, he would just get visibly irritated, which was kind of endearing,” recalled Viall. “I think that kind of was the beginning of him realizing, ‘I really care about this person and I want her in my life and if I don’t do something fast, I might not have that.’ So I’m really glad that he woke up and realized that.”
Viall, who lives with Haibon in Los Angeles, said the new couple is definitely “the real deal.”
“It’s like they’re in high school again. It’s very cute. It’s very intense and sincere,” he said. “They’re the real deal for sure.”
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The giddy duo recapped their journey for fans in a tear-filled episode of Iaconetti’s show The Story of Us, and Haibon admitted Iaconetti’s relationship with Wendt felt like “a kick in the a—.”
“I remember I heard rumors that she might have met somebody, and I was sad,” he said. “Sometimes I need a kick in the a—. That was a big kick in the a—.”
He eventually told Iaconetti about his feelings and after the reality star called it quits with Wendt, they began to date.
“I just knew in my heart at that point that it wasn’t right with Kevin,” she said. “I ended the relationship because it had run its course — and then Jared was still there.”
Haibon’s ex, Caila Quinn, also attended the Smirnoff Red, White & Berry summer kickoff.
—Reporting by Breanne L. Heldman