The 17-year-old singer worries her 20-year-old Australian boyfriend Liam Hemsworth could leave the US, and her, at any time.
In an interview with Ryan Seacrest on his KIIS-FM radio show, she said: "I don`t want to be heartbroken. He could go back to Australia any second. But I`m happy. It`s different from anyone else because he really is just an awesome friend too."
Although the pair have been dating for a year, after meeting on the set of movie `The Last Song-, Miley admits she has a crush on `17 Again` star Zac Efron.
She said:" He`s gorgeous, he`s hot, I don`t go see his movies because I`m like, `He`s such a fantastic actor.` He`s a great actor, but he`s hot."
The `Can`t Be Tamed` singer also spoke about how she is determined to stay away from drugs, but is looking forward to being able to drink when she is old enough.
She said: "I`m not gonna be like, `I`ll never have a drink in my entire life,` because that`s probably going to be a lie. There`s a right way to do so - everything is good in small portions."