He can’t stop, he won’t stop! Back in the day, Miley Cyrus and Liam Hemsworth called off their engagement because of their differing views on her wild child days — but nowadays, it’s the hunky Australian whose partying is out of control. And an insider exclusively tells In Touch that it’s causing a riff between the couple.

“It’s like they’ve switched roles,” the insider tells In Touch. “Miley is begging Liam to reel it in, but Liam really doesn’t want to.” Of course, the irony of the situation — that she’s the one who wants to settle down, while he’s out acting like a party animal — isn’t lost on anyone. The insider adds, “Now Miley is the one who wants to get married and start a family. The situation has led to many bitter fights beween the two.”

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The two can’t even find peace in the home that they share together. Since going sober, the 24-year-old “Malibu” singer has made their LA home a party-free zone — and Liam, 27, isn’t happy about it. The second source adds, “Miley and Liam have always been homebodies. They used to just have friends over and party at home. But now that Miley is sober, their has become a very boring place.”

For now, they’re able to both get their way — by living totally separate lives. Miley is back home in Malibu, while Liam is busy filming a new movie in NYC, where he’s been acting like a “frat boy” alongside his co-stars Rebel Wilson and Adam Devine; the three of them have been living it up — behind Miley’s back. But it’s only a matter of time before the whole thing explodes, the source speculates.

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“Liam’s been living it up in NYC. He has a bunch of friends there. It’s literally like a group of frat boys,” the source explains. “I’m pretty sure Miley won’t be happy when she finds out.”

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