It's over: Heartbroken Khloe Kardashian files for divorce from Lamar Odom after four years of marriage... but puts on a brave face as she heads to the gym

Khloe Kardashian has filed for divorce from Lamar Odom after four years of marriage citing irreconcilable differences.

The reality star, 29, who is being represented by sister Kim's former attorney Laura Wasser, asked to have Odom dropped from her surname, according to TMZ

The couple reportedly have an 'ironclad' prenup and the beauty is asking for no spousal support from the NBA player, 34. She wants the judge to reject any of the former Lakers' requests for support as well.

     
                     
                    
                     
                                    

Wearing workout clothes and carrying both a large bag and a rucksack, the LA native kept her head down as she went in for a therapeutic sweat session - with her wedding ring notably absent from her left hand.

She has not been spotted with her ring on since November 22.

Lamar has not been photographed since November 28

                                         

On Thursday, the Keeping Up With The Kardashians star posted a self-empowering message to her Instagram account, increasing the speculation that the end of her union is near.

'I am strong because I've been weak. I am fearless because I've been afraid. I am wise because I've been foolish,' read the black-and-white note.

                     

Khloe and Lamar tied the knot in 2009, just four weeks after meeting, and have seen their marriage go through a particularly tumultuous time as of late amid allegations of the basketball star's repeated drug use and infidelity.

Also on Friday, big sister Kim was spotted leaving her Los Angeles home early in the morning, dressed in business attire and driving her large black Rolls Royce. 

It is not know whether the 34-year-old was heading to be by her little sister's side or addressing a professional obligation.

                   
                   

Once she is single again, Khloe will remain as the beneficiary on a $10 million life insurance policy Lamar has and that will remain for the rest of their lives. 

Contrary to reports, an insider told the website: 'There is absolutely no cheating clause in document… it just doesn’t exist.'

However, legal ace Lisa Myer, who drew up the prenup, will not represent her during the divorce. Instead it will be Laura Wasser, who represented sister Kim during her contentious split from ex-husband Kris Humphries, who will be by Khloe's side, reported Radar.

                                 
                          

The final straw was said to have come for Khloe when a bizarre freestyle rap video of her spouse openly bragged about cheating on her was posted online on November 22.

A source told TMZ: 'The end was a long time coming. Khloe had expressed dire concerns about the marriage ever since she learned about Lamar's crack addiction earlier this year, but she forestalled divorce for fear he'd overdose or worse.'

Khloe's impending divorce announcement comes just hours after her mother 'momager' Kris Jenner declared her support for her daughter via a touching post on her website. 

Using Khloe's nickname Koko, Kris said: 'Perfection doesn't exist. But I believe in someone being perfectly imperfect. Our imperfections make us all stronger individuals. You are our strength. 

'You at times, think I'm mean to you, I'm not, I'm merely aware that you may be the strongest woman I know. Sometimes I like to test how strong you are and you always amaze me. I love you!'

                        

The divorce comes after Khloe desperately demanded Odom enter rehab after the embarrassing video surfaced.

The NBA star refused, which led the E! star to take off her wedding ring once and for all.

A source revealed to Radar that, 'Surprisingly, Khloe wasn’t upset about the cheating confession, but the video which proved to her that Lamar is continually abusing drugs and alcohol. He was obviously wasted when the video was recorded.'

The latest report comes after it was claimed in US weekly

 on Wednesday that the Keeping Up With The Kardashians star would be filing for divorce 'very soon'.

The brunette beauty was again seen without her wedding ring at The Hollywood Reporter's Women In Entertainment breakfast with mom Kris Jenner and sister Kim at the Beverly Hills Hotel on Wednesday.

With tanned and toned pins and a content smile, the slim star seemed to not have a care in the world during the Audi-sponsored power event.

Pointy white pumps and a smart gold-studded clutch made her look undeniably A list as she mingled with Demi Lovato, her X Factor co-star.

But no matter how amazing she looks at the carpet, there's no denying Khloe's personal life is as bad as it can get.

The root of the problem was that the basketball player wouldn't get help for his reported drug and alcohol problems that don't seem to be ending.

But according to TMZ.com, it was his infidelity comments he made while being videotaped slurring through a rap song with friend Jamie Sangouthai, in November: 'And when Khloe's out of town I still be on the DL.'

'She flip-flopped several times, but she can't imagine having kids with someone who refuses to seek help for his disease,' the insider told Us.

As far as how the athlete feels, he's reportedly 'sad.' 

'She is saying, "I'm moving on,"' added the source.

Will she miss the bling?: The star hasn't worn her wedding rings since November 22

The weekly also reported the sister of Kim has agreed to let her marriage drama be a big part of next season's Keeping Up With The Kardashians, which will premiere in January.

'At first she was adamant about not letting E! address the situation,' the source said.

'Then she realized it would ruin the series' integrity not to show what she was going through.

'But she won't let them air anything that will hurt Lamar too much.'

There have been several tell-tale signs that the couple has been kaput.

In addition to not wearing her mega sparkler, she also purposefully avoided her estranged husband on Monday evening at the Jay Z concert in LA.

     

According to E online the pair sat in completely different areas of the arena, with Khloe opting to mingle with fellow concertgoers while Lamar sat in a private VIP suite with his father Joe and some friends.

During the evening, Khloe looked downcast as she surrounded herself her new BFF Nicki Minaj and old pal Malika Haqq as she tried to take her mind off the drama surrounding her marriage.

On Saturday she posted a note that was addressed 'Dear Human' and insisted people are here to 'learn personal love' and no one is supposed 'to be perfect.'

The entire post read: 'Dear Human: You've got it all wrong. You didn't come here to master unconditional love. That is where you came from and where you'll return.

'You came here to learn personal love. Universal love. Messy love. Sweaty love. Crazy love. Broken love. Whole love. Infused with divinity. Lived through the grace of stumbling. Demonstrated through the beauty of... messing up. Often.

                

You didn't come here to be perfect. You already are. You came here to be gorgeously human. Flawed and fabulous. And then to rise again into remembering.'

Life has not been easy for Lamar this year.

He still has not been re-signed to the LA Clippers, which he has been getting in shape for.

Also, this week he reportedly pleaded no contest to DUI charges stemming from his August 30 arrest.

He was sentenced to three years probation for the misdemeanor in a Los Angeles court. He also agreed to undergo alcohol education courses in addition to paying $1,814 in court fees.

TMZ reports that the basketball forward is required to complete his alcohol education classes by June 9, 2014.