If you thought you’re having a bad week - cheer up! K-Fed is having it much much worse.

On Saturday, he failed to sell ONE SINGLE TICKET to his Webster Hall concert - the venue holds 1,500 and he managed to only fill 300 FREE seats.

Yesterday, K-Fed was sued by Thomas Dolby, who wrote and performed 80’s hit, “She Blind Me with Science” which Kevin sampled for his flop “America’s Most Wanted” without permission.

The dagger in the heart of the FORMER Mr. Spears - Today, his wife Britney Spears filed for divorce (read the petition she filed here) citing “irreconcilable differences.” She is seeking full custody of both children and is not requesting spousal support - good thing, because K-Fed is totally shut out from Britney’s wealth by an iron-clad prenup.

K-Fed is screwed and your week must seem brighter!

Update - Here is an insiders account of what went down this weekend to lead to the divorce filing:

At New York’s Regency Hotel, guest Britney Spears “was in The Library restaurant, sitting at a table that had been set aside for her,” says an onlooker. But as the chair opposite her remained empty, “she started crying.” Insiders tell In Touch she was waiting for her husband, Kevin Federline, to arrive that November 2 night — but he never did.

Earlier that day, Kevin was overheard arguing on his cell phone. According to a family insider, the couple had a blowout over Kevin’s upcoming gig at NYC nightclub Webster Hall. “Britney got mad because Kevin wouldn’t allow the kids to go along with him for rehearsals,” explains the insider, adding that Britney, 24, likes to have their sons, Sean Preston and Jayden, with her as much as possible. But the couple seemed to have put the fight behind them — until Kevin was a no-show at the hotel’s eatery. A deeply upset Britney took drastic action. “She stayed by herself with the kids that night, and Kevin moved to a different hotel,” says the insider.

But Kevin picked the wrong weekend to fight with his famous wife. The night after he stood her up, Kevin was set to launch his concert tour with a performance at NYC’s Stereo nightclub, and Britney was scheduled to introduce him. But the pop princess, who has been her husband’s biggest supporter, gave as good as she got — she didn’t show up at the hotspot.

Throughout the early part of the evening, “Kevin constantly scanned the room, and was checking his Sidekick,” says an observer. “It seemed like he was looking for Britney.” While eating a takeout meal alone at a VIP table, Kevin, 28, told In Touch that he’d been “partying all the time,” during his trip to New York. He added, “I’m really tired, and it puts stress on me and I get irritable.” He denied that he was having family problems, but when another guest asked how Britney and the kids were, he responded, “I don’t know.

At 2 a.m., when it was clear Britney would not turn up, “Kevin performed ‘Playing with Fire’ and ‘A League of My Own,’ ” says a guest. “Afterwards, there was no cheering.” Later, the DJ played Britney’s hit “Slave 4 U” but “Kevin sat stone-faced until he motioned for the DJ to cut the song off early,” says another onlooker. The rapper left the club alone at 4 a.m.

Although Kevin was spotted back at the Regency Hotel on November 4, having seemingly reconciled with Britney, he found himself going solo for the second night in a row. His Webster Hall show drew only 70 fans — and Britney was not among them.

Afterward, a noticeably glum Kevin dined at Corio, where even a burlesque dancer couldn’t seem to cheer him up. At 2:40 a.m., Kevin was still going strong without his spouse. He stopped by Sean “Diddy” Combs’ birthday party at hotspot Marquee. By November 6, Britney and Kevin were even further apart. He flew to Canada to attend a taping of Much Music, while Britney stayed behind to appear on Letterman.