HOLLYWOOD, Calif. — It's over for Rumer Willis and boyfriend Micah Alberti.

The twosome has split after more than two years of dating and a source tells Life & Style that Willis "is very upset" about the broken romance.

"She went to Las Vegas this past weekend with a few friends to try to cheer up and have fun, but she's very sensitive about the breakup," said the insider.

Willis spent her Saturday night partying at Tao in Las Vegas, the sight of her 21st birthday party a year ago. The actress was seen chatting it up with new Glee cast member Chord Overstreet.

Says the insider, "Rumer is doing her best to move on."