United Kingdom, July 7 -- Kim Kardashian's world "is not the same" following the death of her childhood friend.

The 44-year-old star's pal Lindsay May Palevsky - one of her inner circle she calls the 'Lifers' - passed away from a rare form of cancer in November, and the Skims founder felt her loss particularly hard over the weekend, which would have been Lindsay's birthday and was often an opportunity for the group to go away together.

Sharing a series of photos on Instagram, Kim wrote: "It was just your birthday and I know you never liked to make a big deal of it, but Happy Heavenly Birthday, Lindz...

"Nothing really captures how quiet and empty our lifers chat feels without you in it. I know you'd probably roll your eyes at me postin...