The exes, who share two-year-old daughter True, have been spending more and more time together in recent months after they initially split when Tristan was caught kissing model Jordyn Woods at a party, and Kim believes the reason Khloe hasn't made any moves to officially rekindle their romance is that she's concerned about what the public might think.
Speaking to Tristan in a teaser for this week's "Keeping Up with the Kardashians" episode, Kim said, "I don't even think it's up to her anymore about getting over the past things that you guys have been through. I think it's just mostly what other people are gonna think. I think she's totally fine, otherwise she wouldn't be hanging out with you 24/7."
Tristan agreed, replying, "She's carrying a suitcase of other people's opinions and thoughts."
Kim also told the 29-year-old basketball star it's unusual to see her "tough" younger sister so vulnerable, while Tristan said he'd love it if the Good American founder took a leaf out of Kim's husband Kanye West's book.
"Like Ye, he don't give a d**n if you like him or not," he said. "But guess what, he's happy and he's gonna do it his way and you're gonna like him or not. That's why I respect him. You're gonna ride this journey the way you want to... and people are gonna be with you or against you, but at least if you die, you're going to die doing it your way. That's my mentality. And she's gotta understand it too."
Ultimately, Kim believes the key to solving Tristan and Khloe's relationship drama is communication.
She said, "Honestly, I just think that you should talk to her; that you should just tell her you don't want to rush her process, but... that you don't want to be this kept secret because she is so embarrassed."