Brooke Mueller has gone back to rehab following a crazy week of binging ... sources familiar with the situation tell TMZ.
TMZ broke the story ... Brooke refused a drug test Friday, which she was required to take as part of her custody settlement with Charlie Sheen.
Sheen's lawyers are going to court on Tuesday to raise the issue, and we're told Brooke's move is a preemptive strike.
Sources say Brooke disappeared for a time this week during her binging. TMZ obtained surveillance video of Brooke attempting to get money for jewelry at an Inglewood pawn shop.