Matthew Perry has a hard time looking back at his younger self.

The “Friends” star appeared on CBC Radio’s “Q” this week and opened up about his battles with addiction and shared why he can’t bring himself watch the show that made him a star.

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“I had a rule that I would never drink or do drugs while working,” he said of his time working on the show. “Because I had too much respect for the five people I was working with. So I was never wasted while working.”

He did admit to sometimes being “extremely hungover” at work, though. “At one point I was shaking so much that if I was gonna go from the bookshelf to the table, I’d have to quickly do it and put my hand on the table so I wouldn’t shake. It got that bad.”

But when it comes to why he can’t watch “Friends”, it has more to do with how he looked physically at the time.

“I was taking 55 Vicodin a day, I weighed 128 lbs, I was on Friends getting watched by 30 million people — and that’s why I can’t watch the show, ‘cause I was brutally thin,” Perry said.

“I didn’t watch the show, and haven’t watched the show, because I could go, drinking, opiates, drinking, cocaine,” he added. “I could tell season by season by how I looked. That’s why I don’t wanna watch it, because that’s what I see.”

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Getting even more candid, Perry continued, “You know, the thing that always makes me cry — and I hope I don’t cry here — is that it’s not fair. It’s not, it’s not fair.”

He explained, “It’s not fair that I had to go through this disease while the other five didn’t. They got everything that I got, but I had to fight this thing — and still have to fight this thing.”