Kim, 41, who in the past has seemingly tried to keep her personal back-and-forth with Kanye private, has also been speaking out more in recent months as the rapper continues to insult her, her current relationship, and her parenting.
As for how Kim feels about her boyfriend directly confronting Kanye, a source tells ET, "Kim didn't want Pete to make things worse, but she was also glad that he stuck up for her. It is nice that Kim has Pete on her side publicly and privately."
The source adds that the mother of four is "hoping" that her ex will move on and stop publicly attacking her and Pete, but so far that has not been the case.
"Kanye's actions are causing a lot of stress for her," the source says of Kim. "She wants him to stop and not have the kids hear anything or be affected negatively by his antics."
Already the source says that the former couple's eldest child, 8-year-old North West, "hears things from her friends" and has found her dad on social media.
Kim and Kanye are also parents to Saint, 6, Chicago, 4, and Psalm, 2.
As for Pete, the source says he is "really over Kanye and has had enough."
"Pete is at a point where he is not backing down," the source notes. "He needs Kanye to stop and thinks he has gone way too far. Pete is super into Kim, and this is how he is showing it. He is not taking anything from Kanye anymore."
With her family in mind, Kim finds herself in a difficult position.
"Kim agrees with Pete, and if Kanye doesn't stop, she knows she will be forced to take more drastic measures," the source adds. "She just doesn't want anything bad to happen."
As of late, Kim and Kanye have no formal custody agreement in place for their four kids, and another source tells ET that the rapper hopes to change that.
"Kanye has told his lawyer he wants a more formal custody agreement with Kim. The two currently have nothing in place, but Kim has the kids, and Kanye is allowed to see them whenever he wants, within reason," says the source. "Kanye feels he’s not been getting enough time with his children and if his lawyer can’t work something out with Kim will go to court.”
Earlier this week, Kanye claimed that he was being kept from his children on social media, prompting Kim to comment on his post, "Please stop with this narrative, you were just here this morning picking up the kids for school."