In conversation with Dax Shepard and Monica Padman on the Armchair Expert podcast, the singer talked about taking opioids and drinking during his “Blurred Lines” era, but then falling into old habits again in recent years while trying to cope with a lot of loss — of dad Alan Thicke, mentor Andre Harrell and his house, which burned down in the California wildfires. “I lost myself,” he admitted, but added, “I have finally woken up.”

“I just went through my darkest days,” the Masked Singer judge, 44, admitted. “My father, my house, my mentor, my addictions — just everything at the same time all hit the wall. I don’t want to be that person ever again.”

His struggles amid his “Blurred Lines” success in 2013 were well-documented, both during his divorce from Paula Patton and his copyright infringement lawsuit with the estate of Marvin Gaye. During a deposition for the latter, he said using the opioid painkiller Vicodin mixed with alcohol left him in a haze for a full year.

“It wasn’t until my 30s” that addiction problems surfaced, he said. Before, “I was in good control of my faculties. I was a beer and a glass of wine kinda guy. It wasn’t until touring and partying and the lifestyle. You just think you can manage it all. You think you can keep going at that pace. And then your habits catch up with you.”

Shepard, who recently had a relapse with pills, said, “Opiates have the illusion of being manageable, don’t they?”

“Yes,” Thicke replied. “And the illusion of normalcy. Some form of normalcy. You don’t have to hide in the bathroom. You’re not falling down or slurring your words. It’s not on your breath. You can’t necessarily see it in the eyes.”

Thicke said he didn’t want to be “reckless” in his account of his substance abuse — or the timeline of it.

“The ‘Blurred Lines’ stuff was a pill thing. That was pills, drinking, my back was hurting,” he said. “It started from traveling on long flights, back pain and then it just became a bad habit.”

The second wave was “once all that ‘Blurred Lines’ madness stopped and I moved to Malibu [in 2015]. I had a really nice honeymoon [period] with April [Love Geary] for a while,” referring to his now-fiancée whom he started dating in 2014 after separating from Patton. “Then the honeymoon slowed down and the drinking increased.”

It was exacerbated by the sudden death of his dad, star of Growing Pains, from a heart attack in 2016, which was followed by more turmoil: the death of his manager, Jordan Feldstein, in 2017, and then the loss of his house, which burned down in 2018. Professionally he was struggling, feeling like he was “out of the music business,” and, on top of that, he gained 50 pounds.

In that period, “I lost myself,” he admitted. “I was making music that wasn’t even from my heart anymore. That’s where I kind of lost myself for a while.”

It was when he suffered even more loss — the death of his mentor, record executive Harrell, last May during the early months of COVID — that things came to a head.

“It all became very clear,” he said of facing his troubles. “I was functioning. I wasn’t high all day. It was more like: take care of the kids and once they’re asleep I’m going to drink myself to sleep. But then you’re cranky in the mornings. Then you’re arguing with your lady. You don’t remember what you said. Then you’re like: This isn’t a life for a family and I can’t be the dad I want to be like this.”

The father of four added, “I have to change my life.”

Of that whole era, from “Blurred Lines” until last year, “Knowing what I know now, I could have managed it all better. It turns out I had a child inside of me that needed unrealistic things. I had unrealistic desires — and then they got more selfish. The more successful I became, the more selfish my desires became.”