Miley and Liam Rebound Watch: Who Is Eiza González?

What happens in Vegas … sometimes follows you home to L.A.

Reps confirmed to omg! on Monday that Miley Cyrus and Liam Hemsworth officially called off their engagement, although sources close to the situation tell us the former couple have been broken up "for a while now."

So, what are the factors that led to their split?

[Related: Miley and Liam's Road to Splitsville]

By the look of his behavior over the past few days, Liam certainly seems ready to move on.

The 23-year-old actor was photographed cozying up to Mexican actress Eiza González in Las Vegas this past weekend. And, apparently, it wasn't a one-time hang out session! Hemsworth was spotted with the beautiful singer — also 23 — again in Los Angeles on Monday.

While Liam is certainly free to mingle with whomever he pleases, his alleged infidelity while engaged to the "Wrecking Ball" singer has been tabloid fodder over recent months.

But was there a definitive nail in "The Last Song" co-stars's relationship coffin?

Us Weekly continues to claim that Hemsworth was pursuing January Jones in the weeks leading up to his and Miley's breakup, though a rep for the "Mad Men" actress denies this.

If you recall, Liam's relationship with January, 35, was what first sparked split rumors in late February after they were spotted leaving a pre-Oscars bash together.

Sources close to Cyrus even tell E! News that ending the engagement was "Miley's decision, after coming to grips with Liam being what she believed was less than faithful to her."

Yet if Liam's alleged wandering eye is on one end of the split spectrum, then Miley's racy new image is on the other.

Cyrus — who has been busy with her upcoming album "Bangerz" — admitted in March that she "put this record before everything," including personal relationships. Over the past several months, Miley has done everything she can to kill her Hannah Montana image and replace it with that of a twerking party girl … something Liam reportedly couldn't get behind.

The "Paranoia" actor was allegedly embarrassed and shocked by Miley's raunchy performance alongside Robin Thicke at the VMAs in August.

Insiders close to Hemsworth tell omg! he and the singer just drifted apart over the last few months.

"They aren't in the same place they were a year ago," adds a source.

Bottom line: Team Cyrus is blaming the split on Liam's possible infidelity and Team Hemsworth is pointing fingers at the new Miley.

And you know how the saying goes … the truth is probably somewhere in the middle.

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