Friends fear Kanye West abruptly canceled 21 dates on his Saint Pablo tour because he’s “suffering from a nervous breakdown.”

A source close to the rapper told Page Six, “He’s having a nervous breakdown. He’s surrounded by all these crazy people, but there’s nobody he listens to or who can rein him in. He’s spiraling further and further out of control. Basically everything crazy he does is ‘art’ — canceling his tour is ‘art’ — he is becoming more and more unpredictable,” the source said, adding, “His state of mind goes back a long way, perhaps to the death of his mother, which he never got over. That combined with his chaotic life — he often stays up and works for 48 hours at a time when he’s on, and calls his team at 3 a.m. Kanye needs a stronger support system, he needs to take some time to fall to the ground and start from scratch again. He’s so talented, but he’s his own worst enemy.”

Another source explained West is burned out from juggling his fashion line and the tour. “He’s just exhausted. He’s been working around the clock on fashion design, both on his own line and the Adidas line. He’s a notorious workaholic, so balancing both that work — which is extremely important to him — and the rigors of the tour every night . . . really wore him out.”

Last month we reported that Kanye had a “massive meltdown” and fired all his staff after his much-maligned Yeezy fashion show in September, during which models fainted and reviews ranged from “hot mess” to “[an] abomination.”

Plus, other sources tell us that Kanye and wife Kim Kardashian “have been arguing a lot since the Paris robbery.” The source added, “Kim has completely calmed down her life, but Kanye is stubbornly refusing to let fear get in the way of what he wants to do.”

West’s longtime friend Rhymefest, a song collaborator who also co-founded Donda’s House, a nonprofit named after West’s mother, was so concerned about the rapper’s erratic behavior that he quit working with him earlier this year. “My brother needs help, in the form of counseling. Spiritual & mental. He should step away from the public & yesmen [sic] & heal,” Rhymefest tweeted in February. “I love my brother. I pray for his health not our entertainment.”