"[With any] new experience that you have, you don't know how you're doing because you've never experienced it," Duane said with a long pause. "I have a lot of people who depend on me. All my supervisors said, 'Dog, it's time to man up.' So I'm trying to man up."
While it's been an emotional time for him and his family, Duane explained how Beth had tried to prepare him for the moment when she would no longer be by his side.
Dog the Bounty Hunter Holds Emotional Beth Chapman Memorial in Hawaii
"For two to three years, she knew this might happen. So she would say, 'Who is going to sit next to you?' And I said, 'No one,'" he tearfully recalled. "'Big Daddy, you better not let another girl take my place.' I said, 'I won't.'"
As Beth's health took a toll -- in September 2017, Beth shared a moving letter to family and close friends explaining that she had Stage 2 throat cancer -- both she and Duane needed therapy to deal with her struggles.
"I needed therapy and the therapy she used when she was sick was to hunt. Her therapy, you know, was hunting, bounty hunting, catching the bad guy," he shared. It was a "hard" period of time for them as a couple.
"Even though she is not physically there, mentally and spiritually she is there," he added of being on set without Beth.
While he was by Beth's side all through her cancer and witnessed her many ups and downs, it never prepared him for his final moments with her. But Beth was a fighter and one of a kind. "There is not another Beth. There'll never be another Beth. There ain't a girl built like another Beth," he stressed.
Dog the Bounty Hunter Shares Wife Beth Chapman's Final Words
In her final moments, however, Duane told his wife that he was "not going to let her die." "The last few moments she said, 'Come in here right now, in the bathroom,'" he recalled. "I went in and she said, 'Look at me.' And I said, 'Yeah, you're freaking beautiful baby.' [And she said,] 'Look at me, Duane Chapman.' And I did, I always saw Beth and she said, 'Please, let me go.'"
"And I didn't even make a decision, I almost said, 'I can't,'" he continued. "Before I could say, 'Alright,' she couldn't breathe and I called the ambulance… But every day she talked as if she was not there. 'Here's what to do with this, here's what to do with that. Don't keep running your mouth. When they ask you a specific question, just answer that.'"
"So, prepared? No, you're never, ever prepared. You can't prepare," he expressed. "There is no way. I did not know that this was going to happen that day."
Tune in to tomorrow's ET for more from our exclusive sit-down with Duane. For more on Beth's life and legacy, watch below.