January marked the eight-year anniversary of actor Heath Ledger's accidental death from prescription drugs. His untimely passing rattled Ledger's family, friends, and fans. One of Ledger's co-stars, Jake Gyllenhaal, was, and still is, particularly emotional, since Ledger was one of his first friends to pass away.The two formed a close friendship while filming Brokeback Mountain in 2005, and Gyllenhaal, like the rest of the entertainment industry, was shaken to his core upon hearing the news in January of 2008. He still can barely talk about it all, he said in a recent interview with People When asked how the death affected him, Gyllenhaal said, "I don't know if I can answer that in one answer." He continued: "Personally, it affected me in ways I can't necessarily put in words or even would want to talk about publicly. In terms of professionally, I was at an age where mortality was not always that clear to me."Ledger and Gyllenhaal were both 28 at the time of Ledger’s death. Ledger’s death made Gyllenhaal come face-to-face with the brutal realities of the world, and how quickly people can enter and leave your life."I think you live in this bubble, too, of making films... There are real friends, and there is a real community," he explained. "But there is also that new Macklemore album where he says, 'The curtain closes and nobody notices'... I think that's true, and I think that's okay. But I think at the time, I assumed everyone would notice and they did with Heath dying, but I think it gave you the experience of, 'This is fleeting.'”Gyllenhaal says to this day he remembers that life is short, and that the relationships one forms while making a movie can be more impactful than you realise at first. “None of the attention or synthesised love that comes from the success of a film really matters at all,” he said. “What matters is the relationships you make when you make a film, and the people you learn from when you're preparing for a film. That changed a lot for me.”Watch the clip below, and grab some tissues.