"It just kind of makes me question everything that we've had," Booth admits on Ben Higgins and Ashley Iaconetti's "Almost Famous: In Depth" podcast.
On an upcoming episode of Ben Higgins and Ashley Iaconetti's "Almost Famous: In Depth" podcast -- which Us Weekly got an advance preview of -- Booth talks about his ex-fiancée Kaitlyn and her new man, former "Bachelorette" contestant Jason Tartick.
"I'm trying to understand things right now," Booth says. "I guess this goes with her new relationship too. It just kind of makes me question everything that we've had."
"I think just with her moving on so quick, I just have a tough time understanding why she would be putting this out everywhere or blasting it all over the place knowing that it could hurt," he continues.
"I do care about her, so I am happy that she doesn't have to, I guess, deal with, maybe, all the pain and the heartbreak because it seems like she’s moved on and she's happy," he says. "It does make me a little more comfortable knowing that she's not at home at our empty house, so I look at it from that point of view."
"I also think that it's helping me to move on because it does hurt that much, but seeing everything, it does upset me and does make me a little angry, but it also helps me to move on knowing that maybe we weren't right for each other and that I will find somebody down the road that will also make me happy."
Booth and Bristowe were together for almost 3 years after getting engaged on "The Bachelorette." The pair announced they were calling off the engagement with a statement in November 2018.
Booth's full "Almost Famous: In Depth" interview airs on Sunday, January 27.
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