Ben Affleck talks pain of Jennifer Garner divorce, how alcoholism affects his parenting, and more on 'GMA'

Actor and two-time Oscar-winning filmmaker Ben Affleck spoke up Thursday about how his alcoholism affects his parenting, and about the pain of his divorce from actress Jennifer Garner.

In a "Good Morning America" interview to promote his upcoming film "The Way Back," about an alcoholic former high school basketball star with father issues who returns to coach at his alma mater, Affleck recalls having become "sober for a couple of years" in the early 2000s. "And then I thought, 'Y'know, I want to just drink like a normal person and I want to have wine at dinner,' and so on. And … I was able to for about eight years."

But, says Affleck, who has previously publicly discussed his addiction, "I started to drink more and more and more and it was really hard for me to accept that that meant that I was an alcoholic." His late father "was drunk every day and that was just life. Then as that got worse — that was really, really painful. … And I always said, 'That'll never be me. I'm never going to do that.' " Affleck, 47, learned from his experiences "how important it is for me to be sober now during these formative years for my kids."

Affleck has three children with Garner: daughters Violet, 14, and Seraphina, 11, and son Samuel, who turns 8 on Feb. 27. "I took the last half of the year off and I just got to be dad,” the star said. "Drive them to school, pick them up. Go to the swim meet. ... That's where the parenting happens — it's in the cracks. It's in the moments where you're just taking them back from soccer and they say something profound or they talk about how they're really feeling about something. ... And that's what I don't want to miss."

His divorce from Garner, a four-time Emmy nominee for her 2001-06 ABC series "Alias," was a particular blow, he confessed. The two separated in 2015 after 10 years, not finalizing their divorce until October 2018.

"I never thought I was going to get divorced," Affleck said. "I didn't want to get divorced, I didn't want to be a divorced person, I really didn't want to be a split family with my children. And it upset me because it meant I wasn't who I thought I was. And that was so painful and so disappointing." In a statement from him that interviewer Diane Sawyer read on-air after the segment, Affleck thanked Garner "for being thoughtful, considerate, responsible and a great mom and person."

A second part of the interview is scheduled for Friday.