Tom Morello doesn't think he will ever "recover" from Chris Cornell's death.
The Rage Against the Machine star - who also performed alongside Chris in Audioslave - has "so many great memories" with Chris.
He said: "I don't think I'll ever recover from his passing, but we have so many great memories. We played an Audioslave show - the first one in 12 years - in January, so to be able to reconnect with him, both as friends and as musical collaborators, that's something I'm so glad we were able to do."
And the 53-year-old musician was devastated to hear about the death of Linkin Park frontman Chester Bennington too.
He added: "It's insane. It's a horrible loss for the world of music, but also a horrible loss cos they were two ... I didn't know Chester as well, but [they were] two really good people. And both seemed very inexplicable, their passing."
And Tom also called for more understanding of depression and how it affects people.
Speaking about depression, he told Detroit radio station WRIF: "That's a real thing and [you should] make sure that they know you're there for them. We've got to look after each other."
Meanwhile, Sir Elton John previously lamented about the "destructive" nature of artists following the death of Chester Bennington and Chris Cornell.
He said: "It has been a sad few weeks. We lost Chris [Cornell] and then we lost Chester. They were two lovely guys. You know artists are prone to being a little destructive, whether you are an actor or singer or visual artist.
"Sometimes, as Jim Carrey said when Philip Seymour Hoffman committed suicide, 'the noise just gets too much'. It is so awful for someone to be so depressed that they commit suicide, especially when they have families. I just wanted to pay tribute to them, as there by the grace of God go all of us. Just remember them fondly and the music they left. It is totally different music to the one I create but still wonderful music that has entertained millions, including me."