LM Otero/Associated Press

Former NFL quarterback Johnny Manziel said in an interview with Good Morning America he was diagnosed with bipolar disorder.

Manziel, in his first public interview in two years, told GMA he is abstaining from alcohol, which he used to "self-medicat[e]" his depression and bipolar disorder:

"I was self-medicating with alcohol. That's what I thought was making me happy and helping me get out of that depression to a point of where I felt like I had some sense of happiness. But at the end of the day, when you wake up the next day after a night like that or after going on a trip like that, and you wake up the next day and that's all gone and that liquid courage or that liquid like sense of euphoria that's over you is all gone, and you're left staring at the ceiling by yourself, and you're back in that depression and back in that hole, that dark hole of sitting in a room by yourself being super-depressed, thinking about all the mistakes you've made in your life, what did that get me? Where did that get me except out of the NFL? Where did that get me? Disgraced?"

Manziel, 25, has been out of the NFL the last two seasons. A 2014 first-round pick, he was released by the Cleveland Browns after less than two years with the team because of inconsistent play on the field and problems off it.

In 2016, Dallas police opened a domestic violence case against Manziel following allegations made by his ex-girlfriend, Colleen Crowley. He later agreed to undergo counseling in exchange for having the charges dropped.

Alcohol has also impacted Manziel's career. He entered a rehabilitation facility in 2015 and was suspended for the first four games of the 2016 NFL season for a violation of the league's substance abuse policy. Paul Manziel, Johnny's father, publicly described him as a "druggie."

"He's a druggie. It's not a secret that he's a druggie," the elder Manziel told ESPN's Josina Anderson. "I don't know what to say other than my son is a druggie and he needs help. He just hasn't [sought] it yet. Hopefully he doesn't die before he comes to his senses. That's about all you can say. I don't know what else to say."

Manziel said he was diagnosed with bipolar disorder about a year ago, per GMA. The first freshman to win the Heisman Trophy, Manziel said his early success played a part in him being unwilling to listen to those around him.

"I had a sense of entitlement about what I had accomplished at the age," Manziel said on GMA. "For a while, I got so ingrained, caring only about what Johnny wanted, only caring what mattered to me, what made me happy. When I look back at it now, even when I thought I was doing what I wanted, I was miserable."

Manziel said his next goal is to return to football. He has not played since he was cut by the Browns in March 2016 but has a contract on the table from the Hamilton Tiger-Cats of the CFL. The two sides have been in negotiations for more than a month.

"I am coming back from a huge downfall," Manziel said. "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."