Is Miley Cyrus cheating on Liam Hemsworth with Cheyne Thomas?

miley-cyrus-liam-hemsworth-cheyne-thomas-cheating.jpgCan't a girl -- say Miley Cyrus -- loll around a pool with her best friend (and former assistant) Cheyne Thomas (who happens to be a guy) draped over her without everyone jumping to the conclusion that she's cheating on her brand new fiance/super-hottie Liam Hemsworth?

Apparently not. But Miley is already out in front of rumors that picked up steam when she and Thomas were snapped hanging out in Miami on Wednesday (June 13). She's taken to Twitter, along with her mom, to chide anyone who thinks she'd cheat on Liam.

"I miss my mommy and my fiance," tweeted Miley as speculation ramped up. "I love my fiance and he loves me. All the rest is bull****. We get to live a life of happiness no one can take that away from us!"

"so now because I am engaged I can't have a friend of the opposite sex? can't have a friend help me out while I'm working alllll day?" she adds. "maybe YOU would have friends too if you'd get your face out the tabloids & start living your own life :) unfortunate."

Miley's mom, Tish Cyrus, concurs. She tweeted, "So sad that the nasty tabloids have to make up stories to sell their trashy mags. Cant they just leave these 2 alone and let them be happy?"

Duh!

For the record -- Miley and Liam are fine. Liam's in New Orleans working and Cheyne is just a friend. 
Photo/Video credit: Getty Images/Flynet