CHAZ BONO is heartbroken that superstar mom CHER snubbed him as he tries to launch his showbiz career.

Since March 22, Cher’s transgender son has been performing at West Hollywood’s Celebration Theater in a 30-minute rock musical based on the 1989 cult classic “Road House” which starred Patrick Swayze – but Cher hasn’t made it to a single show, The ENQUIRER has learned.

And while Cher may be a busy woman, she’s been managing to find time to play around on Twitter while her son is singing and dancing his heart out onstage.

A source who attended  the April 13 performance had nothing but praise for the former “Dancing with the Stars” contestant, who recently revealed that he’s dropped 60 pounds thanks to an intense mixed martial arts exercise routine and a strict diet.

“You could tell all of Chaz’s hard work has really been paying off, because he had the energy and strength to hold his own next to his very physically fit co-stars,” said the source. “His singing was really good too.

“The audience went wild for him and everyone was cheering him on, so it’s a shame Cher had to miss it.”

But while the crowd was whooping it up for her talented son that night, Cher was goofing off online.

 In early April, after the death of former British prime minister Margaret Thatcher, the 66-year-old superstar was prematurely killed off by Twitter followers who misread “nowTHATCHERisdead” as “nowthatCHERisdead.”

Cher referenced the mistake in an April 13 tweet, joking that she was going out shopping for a black leather motorcycle shroud. And in the days prior, she was tweeting about the progress of the album she’s recording with her own mom, Georgia Holt – at the same time Chaz was onstage!

Cher has mentioned Chaz just once since he’s been performing, when she tweeted a photo of them together at the 44th birthday party she threw for him at her L.A. home…in early March.

“The fact that his mom has snubbed him has completely devastated him,” added the source. “Chaz wanted so badly to show her how talented he is and what a great singer he’s become, but it seems she’s just too busy to make any time for him these days.”