Catherine Zeta-Jones -- Back in the Driver's Seat ... After Leaving Treatment Center

Catherine Zeta-Jones is out of treatment ... and back in control.

For the first time since leaving a mental health facility where she underwent some healthy "maintenance" for her bipolar disorder, the Oscar winner was spotted out in public and driving in New York on Wednesday.

Just yesterday, Catherine's husband Michael Douglas talked to "Extra" about her health -- “She’s got herself worked out with her meds and she's raring to go!”

We broke the story, Catherine entered a treatment facility back in April. She had previously sought treatment back in 2011.