Johnny Manziel Says He Battles Bipolar Disorder, Used Alcohol to 'Self-Medicate'

After years of negative press, wild partying antics and a domestic assault charge, Johnny Manziel says he's in the midst of making a comeback.

The Heisman Trophy winner and former NFL quarterback told Good Morning America that he's taking the steps to protect his mental health over all else.

Manziel revealed that he was diagnosed with bipolar disorder last year ("sometime around June or July") and that he's now taking prescribed medication to cope with it and the depression he found himself in during his fall from fame.

"I am taking medication for bipolar, and I am working to try to make sure I don't fall back into any type of depression," he said during his interview on GMA, "because I know where that leads me and I know how slippery a slope that is for me."

The 25-year-old, who played two seasons at Texas A&M, also said that he would "self-medicate" with alcohol. Since then, he says he's stopped drinking altogether.

"I was self-medicating with alcohol. That’s what I thought would make me happy and get out of that depression," he said.

"When I would wake up the next day after a night like that, going on a trip like that, and you wake up the next day and that is all gone, that liquid courage, or that liquid ... sense of euphoria that is over you, is all gone," he said, explaining how his relationship with alcohol led to his depression. "You are left staring at the ceiling by yourself, and in that depression and back in that hole, that dark hole of sitting in a room by yourself, super depressed, thinking about all the mistakes you made in your life."

One of the biggest factors motivating Manziel to begin his pro football comeback? Seeing others succeed at what he wants to do.

"I am watching all the other guys doing what I want to be doing, and I am sitting on a couch being a loser," he said, adding that "the goal of this comeback is to get back into the NFL, ultimately."

Until then, Manziel is clawing his way into the Canadian Football League while taking responsibility for his past actions and protecting his mental health.

"At the end of the day, I can't help that my wires are a little bit differently crossed than yours," Manziel said. "I can't help my mental makeup or the way that I was created."

"I am coming back from a huge downfall," he admitted. "I don't know what kind of comeback it will be, but I know I want to get back on a football field, to what brought me so much joy in my life."

He believes now his friends and family see "a drastic change" in his lifestyle, and he is hoping to make that change "sustainable."

"Now the question you asked is, 'Is that sustainable?' and 'Would that be the case moving forward?'" Manziel said. "I would like to sit here and say, yes, and I have a lot of confidence that would be the case."