The singer and songwriter was living in squalor in London when his friend died of accidental alcohol poisoning last year, and found her death spurred him to write a number of songs lamenting her.
He told NME magazine: ''When Amy died I was sat in a room, a matchbox room in Camden Town, not able to leave, basically wallowing in my own filth. Literally knee deep in s**t. Literally not able to move.
''I couldn't speak, I couldn't see anyone, I couldn't pick up the guitar, and when I did pick up the guitar it was to write woeful ballads about how Amy wouldn't be coming around tonight. It was an inspiring time.''
Pete also recalled one of the last times he saw the 'Back to Black' singer, after a secret reunion show with his old band The Libertines in August 2010.
He explained: ''She came to The Libertines gig at the Forum. That was one of the last nights we spent together. We came back to the hotel and she stayed all night. At one point it was me, her and Carl [Barat, former bandmate] having a little sing song, and it was all good, you know? Although she was raging drunk she kept insisting she was in The Libertines. We could just step back and do lead and rhythm guitar and she could sing.''