Kim Kardashian West reached her breaking point last year when it comes to her marriage to her husband, Kanye West, sources tell ET.

Amid divorce speculation between the two, a source tells ET that the 40-year-old reality star has actually been "done" with their marriage since July.

"Kim has been over Kanye in a romantic sense for a while but loves him as the father of their kids and doesn't want to embarrass or hurt him," the source says. "Her last real attempt to make their relationship work was when she flew to Wyoming in July and she was seen crying in the car with him. After that, she just knew that she had to be done for good."

"Kim is able to cut things off more easily ... and has reached her limit and she is at a point where she feels like things are done in a romantic sense," the source continues.

Back in July, Kim visited Kanye at their Wyoming ranch after his controversial political rally in South Carolina and his subsequent Twitter claims that his wife and mother-in-law, Kris Jenner, were trying to "lock [him] up." They were photographed having an emotional conversation in their car, during which she appeared to be crying.

The source says Kanye's headline-making behavior last year was definitely a deciding factor.

"Other than the concern for her own family, Kim takes her career, businesses, and image very seriously and keeps that in mind with all her relationships and choices," the source shares. "Kanye's actions have affected all aspects of her life."

Meanwhile, a second source echoes that Kanye running for president last year caused a "huge divide" between the once happy couple.

"She hated the fact that he was running and didn’t feel like he was putting their family first or fulfilling his family duties," the source says. "She felt that his behavior was completely selfish, and it was one of many things that caused her to rethink their marriage."

For the latest on where Kim and Kanye's relationship stands, watch the video below.

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