She told the Observer magazine: "I'd be like, 'I'm not quite sure [where I am], but I'm wearing someone else's clothes...'
"The partying was about me not wanting to deal with the fact my life had changed, not wanting to come down. It always felt like something had picked me up and thrown me around various rooms and houses, then gone 'Boom!'
"It happened every time, and every time it was shocking."
But these days the Hunger singer has curbed her wild antics and it was a "revelation" when she first performed sober.
She said: "When I realised I could perform without the booze it was a revelation. There's discomfort and rage, and the moment when they meet is when you break open. You're free."
And though Florence can still find it hard to adjust after a gig, she loves the fact she can find something special in the "mundane" parts of life.
She said: "Mundane moments become incredibly profound. The performing, the transcendence, then sitting watching TV - all can coexist, and the mundane makes the magical. Maybe I'm trying to hold on to normalcy. Maybe because being onstage has become normal, the pockets of peace seem really wild. But I treasure them."
"Before, I thought I ran on a chaos engine, but the more peaceful I am, the more I can give to the work. I can address things I wasn't capable of doing before."