Caitlyn Jenner makes heartbreaking reveal in new 'Keeping Up With the Kardashians' clip

In a sneak peek of the upcoming episode of "Keeping Up With the Kardashians" on Sunday, which you can watch above, Caitlyn Jenner and Khloe Kardashian have an emotional sit-down to hash out their differences.

The pair was famously close when Jenner was married to Kardashian's mother, Kris, before she transitioned from Bruce to Caitlyn, with their adorable dynamic playing out week after week on the early seasons of "Keeping Up With the Kardashians." In the past few years, though, they've grown apart immensely after drama unfolded between Caitlyn and Kris.

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"I have a ton of opinions and feelings about Cait," Khloe says in the clip. "But, before Caitlyn there was Bruce, and Bruce was in my life for, like, 24 years."

"I just really feel like over the last year and a half, we certainly have grown apart. Day after day after month after month, nobody calls, nobody checks in," Caitlyn confesses to Khloe. "Just, 'Hey, how are you doing?' You can't help but sit there and think, 'Okay, is it because I transitioned? They don't like me anymore?' And I want to know what I did wrong, what I didn't do wrong, what I did right ... and move forward."

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The pair's conversation happens over two big glasses of red wine at Khloe's kitchen table, where they're sitting far apart from one another.

"I don't want to necessarily say you did anything wrong," Khloe responds. "I don't know that just 'cause you didn't do something the way that maybe I would've preferred that that makes it wrong."

Caitlyn's relationship with the Kardashians has certainly changed since her transition. Though she once sat down with her ex-wife, Kris, to hash out their own problems (Caitlyn famously claimed that Kris mistreated her during their marriage when it came to her gender identity), Caitlyn only seems to come around for big family occasions like holidays and birthdays.

"In this family, we deal with things very quickly," Khloe continues in the sneak peek. "We don't take time to really process a lot of things, because we're onto the next. And, for me, at the time, I just wasn't at a place in my life where I could really invest in new relationships. It was very hard for me to experience a lot of new things so quickly and still feel like I had to protect my mom and certain things that were happening, where I felt they weren't the most positive."

"But, then I was like, 'This isn't even my fight to fight anymore. I have my own sh-t to deal with, so why don't you guys figure that stuff out?' But I don't think Caitlyn is a bad person at all."

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Indeed, just a few months after Caitlyn debuted to the world in June 2015, Kardashian's then-estranged husband, Lamar Odom, was rushed to a hospital after overdosing at a brothel. It was a months-long ordeal that ultimately ended in Kardashian going forward with their previously-announced divorce.

"I get that, but that's 23 years of my life invested in the family and you," Caitlyn retorts. "[I was] there when you have good days and bad days for all the things you go through when you're growing up."

"For me, you're all I remember -- Bruce was. So, not having you in my life, it's a huge blow," Kardashian says. "I'm like, 'Okay, my second dad -- this guy that I've grown up with and who raised me -- was taken away from me,' but no one really let me have that."

"Keeping Up With the Kardashians" airs at 9 p.m. EST every Sunday on E!

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