I told myself it was ok to be an alcoholic as I bought alcohol
This suggests the recognition of two mindsets and the interplay between 'them'.
It is very similar to the lens through which addiction is viewed from the RR/AVRT perspective. Have you ever looked into those ideas? There are great threads on those ideas here on SR in the Secular Connections forum.
In AVRT parlance the Beast( the desire for alcohol) is 'speaking' to you via the AV(any thoughts about future alcohol use or doubts about remaining abstinent) and your more rational , truer self initially resists but then ultimately relents and acts on ITs desire. You can recognize and separate from that desire , and dismiss it , not act on it.
The part of your post I quoted shows that you implicitly recognize IT already, you can learn to consciously separate from it . Deciding to never drink again and not change your mind ( the Big Plan) is the catalyst , and it starts immediately , literally right this second, if you want it.
Your AV is telling you that you can't quit , and unfortunately you believe IT, stop falling for the lie, you can, rootin for ya