X17 XCLUSIVE - Britney's "Sick" Of Jason!

We're wondering why Britney and Jason keep spending the night out! I mean Brit's got a beautiful mansion in Calabasas, but these two keep shacking up in Hollywood hotels AND we keep catching these two bickering at each other... At Fred Segal the other day, Brit was yelling at Jason for leaving her alone in the store cafe while he chatted outside on his cell phone. Then on Monday, the two took a spin in Britney's ride, never stopped anywhere, and then went back to the Mondrian where they spent the night. The mood in the car looked super tense ... And then yesterday the couple hotel'd it at the Chateau Marmont. Again, they came out, drove around, and went back to the hotel without stopping. Britney was visibly upset and she was crying to someone on the phone. Our photographer on the scene tells us this:

"Jason wasn't much comfort to Britney. In fact it looked like the two of them had been fighting. Britney keeps him on a short leash -- if you didn't know it, you'd this he was her personal assistant. She's always annoyed with him for doing something wrong or not to her liking. This has been brewing for a few weeks now. It just seems like she's getting sick of him."

Dayum! So, trouble in paradise or a simple lovers' quarrel? How much longer do you think Brit and Jason will last?