Kris Jenner on Nicole Brown Simpson: 'I'll Always Feel Horrible That I Didn't Pay Enough Attention'

— -- Kris Jenner is opening up about her close friendship with Nicole Brown Simpson, and why she says,"I'll always feel horrible that I didn't pay enough attention" about her untimely death.

Jenner appeared as a guest on "The Ellen DeGeneres Show" on Monday, and opened up about her real-life relationships with both Nicole Brown Simpson and O.J. Simpson, as well as revealed details about the aftermath of Brown's death from her perspective.

Jenner and ex-husband Robert Kardashian Sr. were close friends with O.J. and Nicole Brown Simpson, and their relationship is referenced in the FX miniseries "American Crime Story: The People v. O.J. Simpson," which tells the story surrounding the "trial of the century" from the lawyers point of view.

Kardashian served as part of Simpson's legal defense team, and in the mini-series, Jenner, who is played by Selma Blair, and Kardashian, who is played by David Schwimmer, do not see eye-to-eye on Simpson's role in Nicole's death. Jenner revealed to DeGeneres that this depiction was accurate, saying, "It was very difficult because my ex-husband was on one side and I was kind of on the other, and the kids were in the middle."

Jenner also revealed on "The Ellen DeGeneres Show" that she'd actually made plans with Brown to go on a lunch date the day after her death, and believes that Brown was planning to reveal to her that Simpson was abusing her.

"I didn't know that there was abuse until we heard and saw the whole thing unfold like everyone else, and then heard the 911 tapes...which were going to be used as evidence during the trial," Jenner said. "Me and some of her other close friends all were really surprised and shocked by that, because we felt like we really failed her as a friend."

She and I were supposed to have lunch the next day-the day after she was murdered-and she said she wanted to show me some things and talk about what was in her safe," Jenner continued."

"Now, unfortunately, it all makes sense that that's probably what she wanted to reveal to me that next day, which broke my heart because I'll always feel horrible that I didn't pay enough attention."

Jenner,60, had known Simpson since she was 17, and said he was "like a big brother" to her.

The reality-TV star also revealed that Simpson attempted to contact her after Brown's death, but did not give specifics on any conversation they may have had.

"[He called me] right after, yeah," Jenner said. "He called me a few times, and you know, wanted to talk and explain how he felt."

Watch part of Jenner's interview on "The Ellen DeGeneres Show" below: