K-Fed Forced Britney Into Rehab

The latest rumor in Britney’s public meltdown is that a fight with K-Fed over her drug use prompted the head shaving incident, for fear that her hair could be tested and possibly used against her in court for the custody of her two children, the NYDN reports:

According to OK! magazine, it was a blowout with Federline that sent Spears reeling over the edge. “They had a huge argument,” a source told the magazine. “Kevin threatened Britney that he was going to have people test her hair to find out exactly what she’s been up to. She was so scared. That was what made her have her head shaved.” Spears’ friends say the detoxing diva was bowing to pressure from Federline, friends, family and Rudolph, who pleaded with her to return to rehab. A typical stay at the resort-like center, tucked in the Santa Monica mountains, is around 45 days. Patients often share a room, attend group and individualized therapy sessions and do chores. Estimated costs for a stint at the plush facility is between $40,000 and $60,000.

Hit the jump to see some pics of Britney’s first day of rehab!