"Kevin's focus has been on everything but Britney. Instead, he has been putting all of his energy into his music career - which isn't going to go anywhere," our source said.

"Brit is definitely unhappy in this relationship and feels stuck."

In the beginning of the week, Spears also seemed to threaten Federline by printing a thinly veiled poem on her Web site about the "sins of the father."
Source: nypost