LIBERTY ROSS: IDIOT LOOK AT WHAT YOU'RE LOOSING!

Liberty Ross hit the streets of L.A. recently looking good ... damn good ... and her stunning appearance is partly designed to make her cheating bastard scum-bag husband realize he screwed up ... BIG TIME.

Sources close to the couple tell TMZ ... Liberty became "emotionally fragile" after learning Rupert Sanders was hookin' up with Kristen Stewart behind her back.  We're told she was especially hurt by the fact that her husband cast her as Kristen's mom in "Snow White and the Huntsman."

Liberty, who on an ordinary day is a hot sauce model, has upped her hotness since the story broke, and we're told it's partly for self-esteem and partly to give Rupert a searing reminder of what he stands to lose.

Seriously, betrayal is the worst. Its easy to understand why people go nuts by Rob and Liberty both are acting with dignity and self respect. Both amazing catches, while Steward and what's his name...pathetic. 

Liberty has class, because we're told she's not talking about the obvious -- Kristen was a DOWNGRADE!

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