Liberty Ross has filed for divorce from her cheating hubby Rupert Sanders ... TMZ has learned.
Ross just filed her paperwork in L.A. County Superior Court. She's asking for joint custody of their 2 children -- ages 5 and 7.
Ross, who is repped by disso-queen Laura Wasser, is also asking for spousal support, as well as attorney's fees.
Sanders, who is repped by Lance Spiegel, also filed his response to the divorce petition. He's also requesting joint custody. He is not asking for spousal support. As for attorney's fees, he wants to share the costs with Liberty.
Sanders famously cheated on Ross ... with Kristen Stewart, whom he was directing in "Snow White and the Huntsman."
As we first reported ... Ross and Sanders went to a shrinka number of times trying to work out their problems, but it was not meant to be.
Rupert Sanders has proven ... you CAN bang a hot Hollywood actress behind your wife's back and still make it all good again ... and we have the pics to prove it.
Rupert and Liberty Ross shared a great big HUG after leaving a counseling session in Beverly Hills Wednesday. We broke the story ... just weeks after the Kristen Stewart cheating scandal broke, Liberty and Rupert were seeing the counselor.
We also told you ... Liberty went to see a divorce lawyer after the story broke but she has not pulled the trigger and wants to save the marriage.
Our sources say Liberty has laid down some ground rules for any reconciliation ... which includes an extramarital banging ban.
Judging by the hug, it seems they're making some serious progress ... but neither Rupert nor Liberty was wearing a wedding ring at the time of the embrace. They arrived and left separately.
Seems to be the season for forgiveness ... just a few days ago, Robert Pattinson was photographed hangin' out with Kristen.
Liberty Ross looked hot and forgiving Tuesday night ... as she was spotted wearing her wedding ring for the first time since her philandering husband Rupert Sanders was caught cheating with Kristen Stewart.
Liberty was wearing leather pants and her giant diamond ring outside the Chateau Marmont.
Rupert -- who we're told has been "desperate" to save the marriage -- has been seen wearing his ring in the past, but until now Liberty's gone sans her commitment bling in public.
Perhaps all is forgiven.
12:40 PM PT -- Additional photos have just surfaced ... showing Liberty's new ring is actually on her middle finger. NOT her ring finger. Ergo, it's not a wedding ring after all.
Rupert Sanders -- the straying hubby of Liberty Ross -- is "desperate" to save his marriage ... so say sources connected to the famous director.
Our sources say Rupert is begging Liberty to give him another chance, but Liberty is playing it cool. She is non-committal, but our Rupert sources say she has imposed a number of "conditions" that must be met for a possible reconciliation.
As for the conditions ... the easy one is keeping his genitals to himself. Rupert has told Liberty he's down with that. The sources say Rupert has been told in no uncertain terms he must be a better husband. As for whether he's up to the task ... the jury is out.
Our Rupert sources say it doesn't look like there will be an immediate decision on the marriage -- it's likely to take months.
Kristen Stewart has publicly shown remorse over her affair with her "Snow White and the Huntsman" director, but privately she is FURIOUS she's taking all the heat ... sources directly connected with Kristen tell TMZ.
Our sources tell us ... Kristen can't believe the public isn't painting Rupert Sanders as the bad guy. She's grousing that he's 19 years her senior and was "in a position of power over her" ... being a director of a movie she had just shot and presumably someone she was going to work with again.
Kristen is also incensed that she's being called the big cheater. Although she knows she shouldn't have done it because she was in a committed relationship with Robert Pattinson, she feels Rupert is in a totally different and far more culpable situation, being married with 2 kids.
We're told Kristen fears her career may be irreparably damaged -- something she believes she doesn't deserve as a 22-year-old single woman who made a stupid mistake.
The interview just aired ... and RPatz pretty much came to one conclusion -- he needs a publicist asap. But like we told you, he still did NOT bash Kristen.
While eating pints of Ben & Jerry's, Jon joked with Rob ... "Boy, you are better off, kick her to the curb!"
Stewart buttoned up the convo by saying, "When you are young and you break up it's powerful and you feel like the world is ending. This is first time I've seen the world actually react that way. It's insanity." Well said.
Robert Pattinson took the high road in his first interview since Kristen Stewart 'fessed up to cheating on him -- because he did NOT publicly tear her a new one for the scandal.
Pattinson just finished taping his 'Daily Show' interview with Jon Stewart ... and sources in the studio tell us RPat seemed anxious about answering the inevitable Kristen Stewart-Rupert Sanders affair question.
But Rob refused to rip his ex-gf. When Jon Stewart asked how he's holding up ... Pattinson said something to the effect of, "I intend not to say anything."
Jon didn't press further, saying ... "I wish you the best, these things happen when you're young."
Outside the studio ... some of RPat's fans actually booed him as he entered, because his SUV limo pulled in without stopping.
Liberty Ross hit the streets of L.A. yesterday looking good ... damn good ... and her stunning appearance is partly designed to make her cheating bastard husband realize he screwed up ... bad.
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 gorgeous 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.
Liberty has class, because we're told she's not talking about the obvious -- Kristen was a downgrade.
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