The Oscar-winning actor and producer is featured in the February/March issue of AARP The Magazine, and in his tell-all interview, he gets candid about his goals to fix his marriage with Catherine Zeta-Jones and be a good dad to their two children -- Dylan, 15 and Carys, 12.
"You're a fool if you don't get a little more conscious at my age of how you want to spend your days," the Ant-Man actor, who's been cancer-free since January 2011, explains. "It's been five years, and I feel really good, but you have a new appreciation. I'm more motivated, more responsible. My younger kids could be my grandchildren. I want to be here a while."
Now, he's focused on living a healthy life and patching up life at home.
"It took work on both our parts," Douglas says about trying to mend things with Zeta-Jones, 46, after they split in 2013. "I don't think there's much chance of fixing a relationship if one of you is already out the door."
"I think we're both mellower and wiser," adds Zeta-Jones. "That comes naturally with time. We count our blessings."
Douglas also admits that he regrets some of the decisions he made while raising their two children together, along with his eldest son, 37-year-old Cameron, from his previous marriage with Diandra Luker.
"When you're busy all the time, you don't think about a whole lot of things other than the realities that are in front of you," he confesses.
Cameron is currently serving time in a New York prison for a 2010 drug conviction, but Douglas tells the mag that he's paid him a few visits.
"I see him twice a month now because he's incarcerated closer to our home," he adds. "He's a drug addict, but he's done more than his fair share of time for it." He's set to be released in 2017.
It's been a tumultuous time for Douglas as of late, as his mother, Diana, succumbed to cancer last summer at age 92. His father, Kirk, just celebrated his 99th birthday last month, and Douglas knows that it's only a matter of time before he, too, passes.
After his father survived a stroke in 1996, Douglas says he and his dad tightened their bond.
"The crisis opened a new world that otherwise might have passed him by, and helped him do so much good for so many people," he adds. "We're very close now, Dad and I. I feel fortunate having him around long after the highlights of his career."
Back in July, ET caught up with the Hollywood icon, where he opened up about his cancer battle. Press play on the video below to hear more.