The 40-year-old was talking to her mother Kris Jenner on the last episode of the family’s reality show – Keeping Up With The Kardashians (KUWTK).
In scenes shot in October, she said she spoke to a therapist and realized she was unhappy in marriage.
“I just want total happiness,” she said.
“Obviously, I know that complete happiness is not a complete reality, but if I can have it more most of the time, that’s all I want to do.
“Wherever it takes me, I just want my pure happiness, so that’s what I’m working on: figuring out how to get there.
“I just feel like I’ve worked so hard in life to achieve everything I wanted and lived up to my expectations and achieved 10 times more than I thought was humanly possible, but I don’t have a life to share this with. “
KUWTK launched in 2007 when the sisters were largely unknown, but 14 years and 20 seasons later, their business interests are worth billions of dollars.
Kim Kardashian and Kanye West tied the knot in 2014 and share children North, seven, Saint, five, Chicago, Psalm, three and two.
But she explained how lonely she felt after moving to a ranch in the U.S. state of Wyoming while she was staying in California.
She said: “I never thought I was alone, and I always thought it was totally fine, I can just have my kids, my husband is moving interstate. and I’m doing this ride with him and I’m fine with it.
“And then after turning 40 this year, I realized, no, I don’t want a husband who lives in a completely different state from me. I thought, “oh my gosh, that’s when we get along best”.
“But it’s sad for me and that’s not what I want. I want someone who we have the same shows with, I want someone who wants to work with me. “
She said that while she was grateful for the “extravagant” experiences she had had, she was ready for the “little experiences that I think will mean a lot”.
She told her mother not to cry, adding, “I’m numb, I’m sick of it, but I know I’ll be happy. I haven’t come this far just to come this far, and not be happy. “
A special reunion will air later this month and the family have signed a content deal with streaming service Hulu.