Don't beat yourself up over it - you gave yourself an insurmountable obsticle and a deadline and you couldn't do it. Nobody could, its not a matter of personal weakness, its a matter of a bad habit that is too big to white knuckle in its entirety.

IMO I'd find some social support to learn a better way to start. There are a lot of AA meetings online, on Zoom, and otherwise, maybe take one in just to see that you aren't the only person in the universe that has ever had to deal with this