Reality star Rob Kardashian has been struggling for the past two years, but there may be more to the story than just his weight issues.

“Rob is hooked on crystal meth. He’s a drug addict,” a friend tells 'In Touch.'

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“His problems started because of his social anxiety,” an insider close to the family reveals. “He began doing drugs to help cope with everything. But now his issues are all magnified.”

To make matters worse, Rob, 28, is refusing to admit that he needs help. “He’s in pain,” adds the friend. “He’s a total mess.”

For the latest on Rob’s struggle, pick up the new issue of ‘In Touch Weekly,’ on newsstands now!