"She knows Liam has been seeing Eiza and it's been hard for her," a source close to the singer, 20, tells PEOPLE. "She can't believe he moved on so fast and so publicly."
One day after it was announced that Cyrus and Hemsworth's engagement was over, he was spotted in a passionate lip-lock with Gonzalez.
Gonzalez and Hemsworth, both 23, met in Las Vegas last weekend. They were spotted together two nights in a row.
Bruja / Juan Sharma / Pacific Coast News
Asked if the handsome, newly single actor was one of the charms of L.A. (Gonzalez moved there a month and a half ago), she said, "Los Angeles is a city that energizes me. The city is constantly growing and has a great movie culture. Right now, my job is my happiness and I am very happy."
Later, when asked if she felt attacked by the paparazzi due to her outings with Hemsworth, she said, "I didn't feel attacked at all."
"Today I am here on this job and I am happy," she continued. "I have nothing to say about that matter."
This weekend it will be Cyrus's turn to hit Las Vegas, where she's performing at the iHeartRadio Music Festival.