When Keith Urban, 39, took home the best male vocalist trophy at the Country Music Association Awards in Nashville on November 6, pal Ronnie Dunn (of country duo Brooks & Dunn) ran onstage to read a letter penned by the star: "I'm pained not being there with y'all tonight," it said.

Where was he? Us Weekly has learned that, since he entered treatment for alcoholism on October 19, Nicole Kidman's husband of four months has been in an inpatient program at the Betty Ford Center in Rancho Mirage, California, where celebs such as Johnny Cash and Anna Nicole Smith have gotten help.

"Keith is expected to be in rehab for 35 to 40 days," a source close to Kidman tells Us. During that time, he'll attend group therapy, lectures and spiritually focused programs (costs start at $21,000). On November 5, Kidman, also 39, dropped by for a two-hour visit. "They look forward to resuming their life together," says a source. Both stars' reps had no comment.

Talk to Us: Do you think Nicole will stand by Keith?

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