Khloé Kardashian Says She Went 'Ballistic' Catching Lamar Odom Cheating on Her

Khloé Kardashian may seem cool and collected on the outside ... but, even she's lost it a time or two in her life -- admitting she went totally "ballistic" when she found out her ex-husband Lamar Odom was cheating on her when they were married.

The reality television star opened up about the ex-NBA player's unfaithfulness in an interview on "Call Her Daddy" released Wednesday ... specifically detailing when she tracked Lamar and some woman he was with to a motel in Downtown Los Angeles.

Kardashian -- who was married to Odom from 2009 to 2016 -- says she looked through the window when she got there and "saw in the window that him and this girl were ... they were either naked or she was in lingerie, something like that."

Kardashian says she knocked on the door ... and for some reason Lamar and the woman he was with opened up -- and she completely lost her mind.

KK remembers going to Kourtney Kardashian's daughter's birthday party the next day ... with bloody knuckles wrapped up in bandanas acting like "nothing ever happened. And I don't think I ever said a thing." She doesn't say where the blood came from.

Strangely, it seems one of Khloé's other family members might have known about Lamar's cheating anyway ... admitting Kim Kardashian may have known about both Lamar and Tristan Thompson cheating on her before she did.

Worth noting ... Lamar has also opened up about his exact incident -- calling Khloé walking in on him and some girl doing cocaine in a motel "one of the darkest places," and "rock bottom."

Kardashian admits she's in a much better place in her life now ... not feeling the need to tail a partner around L.A. if she was in a relationship.