Khloe Kardashian is sitting vigil at Lamar Odom’s bedside, and is reportedly preparing herself for the worst.

A source tells People magazine the situation looks grim.

“It’s hard for Khloé. He is on his last leg,” the source says.

Lamar Odom was found unconscious at a Nevada brothel on Tuesday and has been on life support ever since arriving at a Las Vegas hospital. There have been no signs of improvement. Khloe Kardashian–as well as several members of the Keeping Up With the Kardashians family–arrived right away. Khloe Kardashian hasn’t left Lamar Odom’s side.

UPDATE – This is just heartbreaking: http://t.co/LxcZ3w5eXM pic.twitter.com/Sit5Z0S8hf

— OK! Magazine (@OK_Magazine) October 16, 2015

“Everyone wanted to hope for the best, but nothing has changed. Now they are preparing for the worst,” the source adds.

Khloe Kardashian has suddenly–and quite unexpectedly–found herself in charge of Lamar Odom’s medical decisions. The two signed divorce papers in July, but due to a backup in the divorce court system, the dissolution of their marriage has yet to be finalized in court. That makes Khloe the legal next-of-kin for Lamar. She may very well be forced to make life or death decisions in the very near future.

“Khloé has always loved him,” the source says. “And that has never changed and if he didn’t have issues, they would be together. She’s devastated.”

'He is on his last leg,' source says http://t.co/VL0l6KFlf6 pic.twitter.com/tjiEcDRT9x

— People magazine (@people) October 16, 2015

Lamar has a history of drug abuse. Some sources say in addition to taking herbal Viagra, he was using cocaine in the hours leading up to his hospitalization. Some reports are saying his condition is the result of an accidental overdose.

Khloe Kardashian is the only one of her family members to remain at Lamar’s side. Mom Kris Jenner and sisters Kylie and Kendall Jenner, as well as Kim Kardashian West, recently left the hospital to return to L.A. Lamar’s children from a previous marriage and his father are there with Khloe.

What will Khloe Kardashian ultimately decide if it comes down to choosing to leave Lamar Odom on life support or pulling that proverbial plug and letting him go?

What a horrible decision that is for anyone to face. What might it do to Khloe if she is forced to decide?