The co-founder of the legendary rock band died on Oct. 6, 2020, after a years-long battle with cancer, his son Wolf, now 33, confirmed on Twitter at the time. Eddie was 65.

Prior to his death, Eddie reportedly became addicted to prescribed steroid pills to relieve swelling after a surgery to remove a brain tumor. According to Alex, Eddie would take more than his prescribed dosage because the pills made him "feel like Superman."

"I didn't see the bottle, but the bottle had, like, a thousand pills in it," Alex continued. "If two's good, 20's better. That was our mantra."

His conversation with Rolling Stone was his first interview since Eddie's death.

"You know, he fought until the end," Alex told the outlet. "Anybody who thought he was anything less than that can suck my you-know-what. ... If you knew what he had to go through to beat the cancer -- he wouldn't do traditional treatment. Some of the off-the-wall s--- caused such a toxic mix in his body. And, yeah, you shouldn't drink with it, Ed!"

The drummer added that his older brother kept making music in Switzerland while undergoing experimental cancer treatments "up to the very end," even though the music he'd begun making "wasn't very good."

"But that wasn't the point. That's what he did," he said.

Alex also shared that Eddie's death caused him to "shut down" in what he described as "oceanic grief."

"I was yelling and screaming. I was beside myself," he said. "I just miss him. I miss the arguments. I live with it every day. And I can't bring him back. I can't make things right."

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Alex's interview with Rolling Stone comes ahead of the fall release of his memoir, Brothers. The book recounts "his life with Eddie from their childhood to the end of the original Van Halen lineup in 1984," according to the outlet.

"We shared the experience of coming to this country and figuring out how to fit in," the book reads. "We shared a record player, an 800 square foot house, a mom and dad, and a work ethic. Later, we shared the back of a tour bus, alcoholism, the experience of becoming successful, of becoming fathers and uncles, and of spending more hours in the studio than I've spent doing anything else in this life. We shared a depth of understanding that most people can only hope to achieve in a lifetime."