While Khloe has kept a vigil by Lamar's hospital bedside ever since he
collapsed at a brothel last week, James is supporting her from afar.
"He is so nice and being as supportive as humanly possible given the situation. Lamar essentially has zero consistent family other than the Kardashians, and James understands that," a source told PEOPLE:
"The last thing he would want to do would be to add more stress to her plate."
James - who started dating Khloe in June - has let Khloe know that he is there for her but has not travelled to Nevada, where Lamar is in hospital.
The insider added: "He never had any intention of going to Vegas. He supports her of course, but understands she needs space and to be with Lamar."
Doctors have reportedly told Lamar's close friends and family that his recovery will likely be a long and difficult journey as the amount of permanent damage to his body is yet to be determined.