When accusations surfaced that Tristan Thompson cheated Khloé Kardashian, a relative tells PEOPLE that the scandal "has been slow to arrive".
Thompson, 27, was spotted spending Saturday night flirting with an unidentified brunette at the PH-D Lounge New York City in video footage and photos taken by Daily Mail .
TMZ and The Shade Room then posted a video of Thompson and a brunette supposedly entering her hotel at 5 am
TMZ also posted images recorded in October 2017 that supposedly represented Thompson kissing a woman while a woman he was groping him in the Darna Hookah room outside of Washington DC
"Tristan has been constantly cheating Khloé," a source tells PEOPLE. "He's a serial cheater, and there will be more women to get out of woodwork."
RELATED: Khloé Kardashian's boyfriend got too close to another woman just before giving birth?
It's a devastating situation for the mother The future, who is nine months pregnant with a girl.
"First Lamar tricked her and now Tristán", says the insider. "Has been through a lot".
Representatives of Kardashian and Thompson did not immediately respond to PEOPLE's request for comment.
The KarJenner clan is crushed by their future mother, says the source. "They're heartbroken by Khloé, they did not realize how deceptive Tristan really could be."
RELATED VIDEO: Pregnant Khloé Kardashian begins nesting in Cleveland and her family will fly in "When is baby"
Although it is not clear if Kardashian knew her supposed infidelity, a source close to the family tells her to PEOPLE that simply focused "on the positive".
"As far as she knew, there were no negative aspects," says the insider. "Once she made the decision to commit, she was inside and trusting"
The friend of the family says that the star "Keeping up with Kardashians " was beyond the head "with Thompson.
" He was his everything. They had a life together. He honestly thought that he treated her like gold, like a queen, "says the source." [He] gave her everything, fell in love with her, told her how beautiful she was. For her, life was perfect. And everything fell apart. "
Kardashian has been nesting in Cleveland with the NBA player as they await the arrival of their daughter. A source told PEOPLE earlier that she plans to give birth there, and her famous family will fly.
"I'm with Tristan and I have my time at home: cooking, being with my love, and just more than one routine," she wrote in her application and website. "In LA, I'm WONDERFUL with work, but again, I love being in New York because I can see my sisters and my mom, and I have my coach and the people that I have grown up with. both cities for me! "