Brooke Mueller: Fine, I'll Go to Rehab

Brooke Mueller is finally admitting she has major substance abuse problems ... and has agreed to re-enter rehab after her cocaine arrest last week -- TMZ has learned.

Sources close to Brooke tell TMZ, she was reluctant at first -- but friends eventually persuaded her she needed help ... and another stint in rehab was the only option.

We're told Brooke's team is now finalizing the arrangements at an undisclosed treatment facility ... somewhere close to her L.A. home -- and she'll be packing her bags soon.

According to sources, Charlie will be taking care of the kids while Brooke is away -- with some help from her parents.