Though there have been rumors about his infidelity in the past, this marks the first time Khloe has openly said that the NBA star cheated on her.
In the shocking episode, Khloe airs her frustrations to sister Kourtney about Lamar's interviews claiming that he still has love for Khloe, 30, and that he's still wearing his wedding ring.
"F**k your ring, you were wearing it when you were fu**ing someone too," she says.
And to add insult to injury, she alleges that she gave up Beyonce tickets on her birthday last year to cover up his infidelity.
"Let me tell you something -- last year on my birthday, I lied to everyone, because I had to lie and say I was with my husband, when in fact my husband was missing with another girl, OK?" she yells. "And I lied, and I gave up my Beyonce tickets to Kendall, that's how badly I was hiding. And In didn't have a birthday, I was alone, and lied to everyone."
This year however, she's clearly going strong with French Montana, who Instagrammed this picture of her derriere Thursday.