The “Malibu” singer, 25, took time out from her vacation in Hemsworth’s native Australia to post a sweet birthday message on Instagram Friday.
“Happiest birthday to my very best friend on the entire planet! I u!” Cyrus captioned the post, which featured three candid snaps of the couple cuddled up together.
Hemsworth turned 28 and is celebrating his birthday on the Gold Coast, Queensland, where he and Cyrus are holidaying along with his parents.
The couple — who first began dating after meeting on the set of their 2009 Nicholas Sparks romance movie The Last Song — were seen soaking in the Aussie sun on Thursday, walking around hand-in-hand.
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But even though the lovebirds are happily engaged, Cyrus has openly talked about her feelings on marriage in the past, making it very clear that she can’t see herself walking down the aisle anytime soon.
The Daily Mail previously reported that she told The Sun on Sunday newspaper in September that she doesn’t “envision marriage.”
“I’m 24. I hope I get to live a little bit more. I have too much living to do ,” she said. “Three years ago, if you’d asked me if I’d be here, this happy with this man, I’d have been stunned. I’m just riding this out. In some relationships, you lose yourself by being with someone else. Actually, it made me find myself more. I have no idea what the next three years will bring, but if it’s possible to get even happier, I’ll take it.”