The Keeping Up With The Kardashians star uploaded a picture of herself and a friend posing with a giant lipstick, alongside the caption: "My spirit animal right huuuuuur #BigHairDontCare."
She also tweeted: "I love you! Thank you for loving me!"
Khloe's messages came on the same day one US source claimed Lamar had left a rehab centre one day after voluntarily checking himself in – and another claimed he'd never entered at all.
According to People magazine, the basketball star checked into a facility on Wednesday morning and left on Thursday afternoon.
But The Hollywood Reporter has cited sources claiming Lamar never checked into a facility in the first place.
I love you! Thank you for loving me!— KhloéKardashianOdom (@KhloeKardashian) September 6, 2013
Lamar's rep has not responded to Reveal's request for comment.
Khloe and Lamar have had a difficult few weeks because of reports in the US of trouble in their marriage. They tied the knot in September 2009 following a whirlwind one-month relationship, and appeared to have proved critics of their union wrong when they celebrated their third wedding anniversary last year.
Neither Khloe nor Lamar have commented on the rumours.
Lamar has also been hit by US reports claiming he is battling a drug problem but, again, reps for the couple have not responded to the allegations.