Bam Margera Is 3 Months Sober Thanks to Reality TV

Bam Margera is bouncing back from rock bottom, quitting booze cold turkey ... and crediting a doctor he met on reality TV for his sober streak.

Bam's mom April tells us he's been sober for 3 months after getting treatment from Dr. Jenn Mann on her VH1 series, "Family Therapy with Dr. Jenn."

We're told Bam's drinking habit played a part when got knocked out cold in June during a concert in Iceland. Still, April says she was stunned Bam agreed to do the show because he'd been on a years-long bender following the tragic death of his best friend, Ryan Dunn, in 2011.

Bam's a completely different person after his treatment with Dr. Jenn, according to his mother ... who calls the change an absolute miracle.