So what does her ex think of her indiscrete latest romp, which follows hot on the heels of her failed affair with Kaitlynn Carter?
WATCH: Miley Cyrus BUSTED getting hot and heavy with Cody Simpson
‘[Liam] really doesn’t care anymore,’ a source told Radar Online. ‘She’s free to do what she likes; Liam is done with her.
‘I don’t know if this is her way of trying to get back at him, but he made his decision.’
It seems that Liam was well and truly over Miley after her tacky flaunting of her fling with Kaitlynn so soon after her marriage imploded. With the pain now gone, it seems that he could not care less about his estranged wife’s latest romance.
‘That is not something you do when you care about a person, let alone your husband who you are legally married to,’ the source told Radar.
Now Liam is working to ‘put all of this behind him’ and is focussing on career and family.
‘Miley Cyrus has always been my childhood celebrity crush,’ he told Fuse in 2012 when he was only 15-years-old. ‘I know all the words to her songs, I'm not gonna lie. I'm not ashamed about it at all.’
WATCH: Cody Simpson says he's been in love with Miley Cyrus for YEARS
‘I was a big Miley Cyrus fan and I think she will be forever the most date-able Disney star.’
Miley attended Cody's 18th birthday bash alongside Selena Gomez and Gigi Hadid - who Cody was dating at the time.
‘Miley is one of my best friends and she helps with some of that transitional stuff—trying to escape your childhood,’ Cody said in 2015. ‘She's super open-minded and I'm working on becoming more like that.’
WATCH: The moment Miley Cyrus SNAPS at Liam Hemsworth