Khloe Kardashian gave Lamar Odom one last chance to choose between her and drugs -- and he's apparently chosen her.

According to Radar Online, Lamar is willing to do whatever it takes to keep Khloe by his side, and has even agreed to take drug tests whenever she asks. A source says, "Lamar has stopped hanging out with his shady drug friends, and has cut off all contact with them. There was a time when Khloe would call Lamar and he wouldn’t call her back for hours, or even days, as he would disappear on drug binges. She knows this is a disease, and Lamar wouldn’t have cheated on her had it not been for his addiction. No pun intended, but the ball was in Lamar’s court, and he has stepped up and is trying to do the right thing.”

Earlier this week, Khloe, Lamar and the Kardashian clan were all spotted together at aKanye West show in L.A.