She has played the part of dutiful wife for over two years now.
But on Sunday's episode of Keeping Up With The Kardashians, the 35-year-old reality star let down her husband Kanye West when she didn't make it to his music video shoot when in Iceland.
'I usually have my s*** together,' said the mother of two after relaying that he was annoyed at her.
It all started when Kim persuaded Kourtney to celebrate her 37th birthday in Iceland where she was going to support husband Kanye West shooting a video.
But on Kourtney's actual birthday they had so much fun sightseeing - including locals singing 'Happy birthday' as she stopped at a hotdog stand - that they ended up missing Kanye's shoot.
Saying she was 'heartbroken,' Kim admitted: 'He's being nice and kissed me and it's all good but I just know he's probably disappointed in me.'
Later, Kanye - clearly in a foul mood - walked away from the table where the friends were eating, leaving Kim's friend Jonathan Cheban asking: 'Why he mad?'
'He's annoyed that I didn't see him perform. So, today was my fault,' she said.
'We flew all the way out here for him, and I did say from the beginning my number-one priority is the video.'