What was the breaking point when you knew you couldn't work anymore?

Mainly asking out of curiosity. I am having a pretty hard time with my migraines lately. My MIDAS score is in the "severely disabled" range, but I know most of us push through, especially in the US capitalist hellscape (I certainly have been). So it made me wonder about others' experiences of when you knew it just wasn't possible for you to hold a job anymore (regardless of getting SSDI or not).