The Smile hitmaker is gearing up to unveil her third record next month (May14) after taking a four-year hiatus to start a family, and she is dedicating the project to Winehouse, who shot to fame around the same time as Allen in 2006.
Allen tells Britain's Daily Telegraph she had watched in horror as the pressure of stardom took its toll on her contemporary, saying, "She was not in a great place when we knew each other, so I don't feel I knew Amy; I knew a version of Amy.
"What she had to deal with was 10 times anything I had to deal with. She'd sold a hell of a lot more albums than me, and there was a lot more interest in her. There were people outside her home 24 hours a day, seven days a week. I know what that felt like on a much smaller level, and I felt trapped... She was all about life and enjoying herself and socialising, and when that's taken away from you... she was a prisoner."
Winehouse died from alcohol poisoning in 2011.