While Rob has publicly made his beef with the 34-year-old reality superstar known -- comparing her to "the b**ch in Gone Girl"
last month -- Kim has insisted on Keeping Up with the Kardashians
that their conflict is due to her being the only one in the family to show him some tough love.
"He obviously has some kind of depression," Kim said about Rob in a recent episode, who according to their mother Kris has gained 100 pounds over the last year
. "He is the king of excuses ... I'm the only one that's really tough with him so he probably avoids me the most."