Since Miley Cyrus and her new girlfriend, Stella Maxwell, have been getting their PDA on, we've been left wondering what Miley's former-fiance, actor Liam Hemsworth, thinks about the romance. 

However, it has now emerged that the 25-year-old Melbourne-native is playing it seriously cool – reportedly telling a friend that "nothing" about the controversial singer surprises him anymore. 

An insider told HollywoodLife.com that Liam "is aware" of the relationship, but that "nothing surprises him anymore with Miley". They added: "But he is not heartbroken, he has moved on."

While Liam might not be crying himself to sleep over the Wrecking Ball singer’s new romance with a Victoria’s Secret angel, the rest of us are just a little bit obsessed with them!

Reports have also revealed that the 24-year-old model, whose parents are from Belfast, has already met Miley’s parents, Tish and Billy Ray Cyrus, and that things are getting serious.

“Miley brought Stella home to meet her family and they really like her,” another source explained. “Her parents are both on board because they see how happy Stella is making her.

"They’re happy that she’s happy, and that’s all that matters to them.”

Miley and Liam first met in 2009 when they were filming the Nicholas Sparks' movie together, The Last Song. They began dating while they were filming and dated for nearly four years. The couple, who became engaged in June 2012, called off their wedding in 2013.

Despite the rumours, the 22-year-old singer has only had great things to say about the Australian heartthrob, and vice versa.

In an interview with Australia's Sunday Night television show Miley said, "I love Liam. Liam loves me." Meanwhile The Hunger Games star has always maintained that they will remain "best friends." 

Miley had since been linked to Patrick Schwarzenegger, but the pair split up in April after five months of dating.