Miley Cyrus
Miley Cyrus at the 2013 MTV Video Music Awards at the Barclays Center in Brooklyn, N.Y. Sunday night. Reuters

Liam Hemsworth was not at the MTV Video Music Awards Awards on Sunday, and it may be for good reasons, after his fiance Miley Cyrus disgusted many viewers with her raunchy performance. Wearing latex underwear, Cyrus stuck her tongue out as she twerked on Robin Thicke during a rendition of “Blurred Lines,” nuzzled his neck, and touched his groin with a giant foam hand.

The 23-year-old Australian actor has kept silent about the performance, but his friends say he is certainly having second thoughts about walking down the aisle with the new twerk queen.

“Liam really does care about Miley, but her racy new look and sort of ghetto attitude isn’t exactly what he signed up for,” a friend tells RadarOnline. “Her VMA performance absolutely mortified him and he couldn’t be more embarrassed. He doesn’t really see anything sexy about what she did on stage.”

Hemsworth proposed to Cyrus in May 2012 with a 3.5-carat diamond ring, but it's been speculated for the past few months that they have been having relationship trouble. They began dating in 2009 after co-starring in the film “The Last Song.”

But since 2009, the singer’s image has changed drastically, and sources say that is hurting the relationship. “It’s not just Liam that Miley is pushing away. … His entire team is urging him to part ways with her because she’s nothing but negative for his reputation and career,” the source said.

“Liam is a serious actor with a growing career, while Miley has just turned into a joke.”