As allegations that Tristan Thompson cheating on Khloé Kardashian surfaced, an insider tells PEOPLE the scandal “has been a long time coming.”

Thompson, 27, was spotted spending Saturday night cozying up to an unidentified brunette at the PH-D Lounge New York City in video footage and photos obtained by the Daily Mail.

TMZ and The Shade Room then published a video of Thompson and a brunette allegedly entering his hotel at 5 a.m.

TMZ also posted footage recorded in October 2017 allegedly depicting Thompson kissing one woman while a different woman groped him at the Darna hookah lounge outside of Washington D.C.

“Tristan has been consistently cheating on Khloé,” a source alleges to PEOPLE. “He’s a serial cheater. And there will be more women to come out of the woodwork.”

RELATED: Did Khloé Kardashian’s Boyfriend Get Too Close to Another Woman Right Before She Gives Birth?

It is a devastating situation for the mother-to-be, who is nine months pregnant with a baby girl.

“First Lamar cheated on her and now Tristan,” the insider says. “She’s been through so much.”

Kardashian and Thompson’s reps did not immediately respond to PEOPLE’s request for comment.

The KarJenner clan are crushed for the mom-to-be, the…