Charlie Puth Mourns Friend Mac Miller: 'I Always Thought I'd Be the One to Help Him Get Clean'

Charlie Puth is remembering Mac Miller after the rapper’s tragic death.

The “Done for Me” singer, 26, told E! News about his friendship with Miller in an emotional interview.

“I had known him for about six months, but we became really close. We became really good friends,” Puth told the outlet. “I always thought I’d be the one to help him get clean and to lead him onto the path of a good, clean, sober life.”

He recalled learning that Miller had died. He said, “Every time someone close to me passes away I always text their phone and — I don’t know why I do this often — I just wrote, ‘I love you man,’ and I knew he wasn’t going to write back, but I just felt like I had to do it anyway.”

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Miller died at his home on Friday. A source told PEOPLE that Miller went into cardiac arrest after an apparent drug overdose. The official cause of death is yet to be determined.

“Malcolm McCormick, known and adored by fans as Mac Miller, has tragically passed away at the age of 26,” his family said in a statement provided to PEOPLE. “He was a bright light in this world for his family, friends and fans. Thank you for your prayers. Please respect our privacy. There are no further details as to the cause of his death at this time.”

Puth and Miller reportedly bonded because they both worked out with trainer Harley Pasternak. “We talked almost every day, and I don’t get a lot of friends who come into my life who I hit it off with so quickly,” Puth told E! News.

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On Friday, Puth tweeted, “I can’t keep losing friends like this…I wish I spent more time with you these past weeks…I’m so sorry… rip MAC…you wrote the soundtrack to my college years and I’m so happy I got to know you…this sucks this really really sucks.”

In February 2016, Miller got candid about his drug use in a documentary called Stopped Making Excuses. “I get f—ed up, let’s keep it real,” he said. “I get super f—ed up, still, all the time. That will never stop. But I’m in control of my life. I’m not f—ed up right now. I’m chillin.”

He continued, “I’d rather be the corny white rapper than the drugged-out mess that can’t even get out of his house. Overdosing is just not cool. There’s no legendary romance. You don’t go down in history because you overdosed. You just die.”

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Puth shared more heartbreak on the 17th anniversary of Sept. 11 on Tuesday. Posting a picture of a handwritten note, he explained, “17 years ago today I wrote this in my diary when I was in 4th grade. #NeverForget.”

The diary entry started, “Dear diary, Today was a bad day.” He noted, “It’s sad but we must go on! We are a strong country.”