SUPERSTAR Cher snubbed her son Elijah Blue twice – first when he was deathly ill and again when he recently wed his German fiancee – he reveals in an explosive interview.

“I’ve always been the black sheep of my family,” Elijah told The ENQUIRER. “We have lots of ups and downs, and now isn’t the best time.”

The renegade offspring of the “If I Could Turn Back Time” singer and rocker Gregg Allman married Marie-angela “Angie” King on Dec. 1 at their new Beverly Hills home – but, in­credibly, Cher has so far refused to congratulate them on their engagement or marriage.

When The ENQUIRER learned of the quickie wedding, we went to 37-year-old Elijah for confirmation, and he revealed for the first time the heart-wrenching details behind his painful relationship with his world-famous mother and most recent battle over Angie.

“We had been engaged for a month and she knew it,” said Elijah. “I wasn’t going to wait for anyone’s approval.”

Elijah and 26-year-old Angie had been living temporarily with Cher in her Malibu compound, BUT at the end of October they moved out after things got ugly. And Elijah hasn’t spoken to his mother since then.

“It’s like a Mexican standoff, but we have a history (of not talking),” he revealed.

Things got so bad Eli­jah and Angie were not even invited to the family Christmas celebration at Cher’s house.

Angie took the rejection hard, saying: “I was very hurt. Christmas is supposed to be about family, and we’d just gotten married.”

But Cher may be risking her future happiness by being so stubborn.

“Elijah and his wife are planning to have children, and if Cher wants to have any part of her grandchildren’s lives, she is going to have to make some major changes,” said a source.

Angie seems to just be the latest bone of contention between Elijah and his mom. They weren’t close as he grew up. After attending boarding schools and military school, Elijah ba­sically went into the family busi­ness by forming a rock band. How­ever, he soon got hooked on smoking heroin and taking painkillers, and he has been in and out of rehab “several times.” He says he last used heroin in autumn 2008.

“My drug addiction was pretty much about an eight-year thing of really heavy using. I was taking lots of drugs on the road. I was smoking dope (heroin), taking a lot of pills, any painkiller we could get and drinking.”

Happily, he’s finally turning his life around and launching a reality show with the love of his life Angie – but behind the scenes, the drama with Cher, his transgender half brother Chaz Bono and absentee father is far from over.

Despite his prob­lems with Cher, Elijah says she’s tried to be a good mom and he remains hopeful of mending the rift with her.

“I know her intent has been genu­ine,” he said. “I know it’s a real regret that haunts her.”

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