The reality star's confidence has been knocked since he started piling on the pounds and he is said to have felt so ''insecure and depressed'' that he shunned his older sister's star-studded ceremony at Forte di Belvedere in Florence, Italy, just to avoid being in the family photos.
According to TMZ, the 'Keeping Up With The Kardashians' clan were devastated when Rob opted to fly back to Los Angeles from Paris on Saturday (25.05.14).
Upon arriving in LAX, the sock designer ignored the paparazzi's queries about why he wasn't at the wedding of the year and avoided eye contact as he texted on his phone.
This report comes after the 27-year-old star - whose problems started following his bitter break-up with Rita Ora in 2013 - allegedly got into an argument with Kim over her lavish wedding extravaganza, which he branded ''superficial bulls**t''.
Things kicked off between the siblings during a lunch at designer Valentino's Château de Wideville in Crespières, France, and Rob headed for the airport shortly afterwards.
An insider told HollywoodLife.com: ''Rob is not in a good place right now at all and his family should be very worried about him. He was embarrassed to go to the wedding in the first place because of his weight gain and to be ridiculed by Kim and basically rejected has put him over the edge.''
Following their fairytale wedding, Kim and Kanye jetted off to Cork, Ireland, to enjoy a five-day honeymoon at a ''luxury private estate'' in the country.
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