Courtesy of Denise Truscello/WireImage
What's a girl to do after she breaks off her engagement?
If you're Kelly Osbourne, head straight to Sin City!
After announcing she was splitting with fiancé Luke Worrall on Facebook and making cheating allegations on Twitter, Kelly packed her bags and headed to Vegas, where she was celebrating her best friend Blake Wood's birthday.
And despite her fresh heartbreak, Kelly seemed "really happy" during her night out, according to eyewitnesses...