I so hear ya...I have had the same experience you describe in the "bam...I'm drinking today" thing. No debate. the decision has been made. Often for me w/o any warning whatsoever. After this last time, I haven't had that happen though and it has been some years. I don't know why that is except to say I will never do it again....so that's really no help to you right now. I think the crucial thing here is that you are talking about what is happening to you and you are on guard. Have you done that in the past prior to the "bam" thing? maybe just getting it out there will really help.
I thought this was very interesting....maybe it will help in some way:
If you are not conscious of all of the different parts of yourself, the part of yourself that is the strongest will win out over the other parts. Its intention will be the one that the personality uses to create its reality.
== Gary Zukav, Seat of the Soul
It sounds like you are very conscious and that in itself is powerful. Your courage is inspiring. Hang in...