But fortunately, she has her dad's support.
"Liam's a great guy," Billy Ray Cyrus told "Entertainment Tonight Canada" on Wednesday (via People). "I like Liam a lot."
In fact, Hemsworth, 22, sought Billy Ray's approval before proposing. "We talked about it a couple of times," Billy Ray says.
Ultimately, Bill Ray reveals his primary concern is that no one winds up with an achy-breaky heart.
"The main thing for me is that both of them are happy," he says. "Miley's worked really hard, and I'm enjoying right now seeing her so happy."
"She and I always had a mantra," he adds. "And the mantra was: if you ain't happy, it ain't working."
Though Miley briefly had fans worried about her state of mind when she tweeted a series of sad-sack comments in September, she seems to be back to her fun-loving self this week, posting photos of her and little sis Noah engaging in Halloween high jinks (sans pants).