Ben Higgins is opening up about his past addiction to painkillers.

The former “Bachelor”, 32, joined “Addiction Talk,” a Facebook Live program hosted by American Addiction Centers, ahead of the release of his memoir, Alone in Plain Sight: Searching for Connection When You’re Seen but Not Known, and detailed his secret battle with addiction.

According to Higgins, his previous battle with prescription pain medications began after he underwent knee surgery as a teen.

During the episode, the reality star says starring on season 20 of the hit dating show gave him “insight into what vulnerability can do when done in an appropriate way.”

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“That gave me a new seeded kind of confidence in being vulnerable and then I knew there was one other thing that was really sitting there on my heart that I’d never shared — like you said, with family, with friends — was my struggle with addiction,” he said on the show. “And not just the addiction piece, but my struggle on where the addiction came from.”

“When I was young … I was a sophomore in high school, we would experiment, like, we would find at the time, like Tramadol, and we would take a bunch of those. But then it kind of stopped. It wasn’t really a thing in my life consistently after that,” he added. “I was already struggling with this lack of identity. And when I took the medication, I remember it being a numbing moment for me, like, when I was high, the depression or the mind, like, my mind wouldn’t wander, it just made me feel number or more maybe, even I can say, like, at peace, and so I just took them then to just rid myself of the pain emotionally that was inside of me. That was the start.”

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After a while, Higgins says he “started to feel a ton of depression, a ton of anxiousness around, ‘Where was I gonna find the next pill’ … and then doing that around friends and family who loved me, it started to click.”

But his final tipping point was stealing pills from his grandfather.

“And then there was a final day: I took pills from my grandfather and I remember the moment,” said Higgins. “I did and I remember doing it and walking out and I just remember this feeling of like, ‘Who are you? Like, what is this about? Why are you still doing this? And you’re taking something from somebody that needs it and someone that you love.’ And that was I think the start of me starting to say, ‘I need to start at least confronting it.'”

Alone in Plain Sight: Searching for Connection When You’re Seen but Not Known is on bookshelves now.