Miley, 20, spent most of her spell in the sun chatting seriously on the phone in Palm Desert, California, reports thesun.co.uk.
Dressed in a floral bandeau bikini, she looked glum.
It's thought Miley had booked herself a holiday for one to clear her head in the aftermath of her break-up with Hemsworth.
Photos: Akshay Kumar, Taapsee Pannu promote 'Naam Shabana'
Flashback: When sexy models sizzled in bikinis at Tokyo fashion show
Photos: These Indian cities top the list in online purchase of sex products
In pictures: Indian-origin artistes in Hollywood
Photos: Varun Dhawan and Alia Bhatt at studio in Bandra