I can relate, Bear. This was me for many years before my alcoholism really got out of hand. I'd make a decision every year (or month or week or day as it progressed). And I believed it also. Thought this time would be different. Thought I'd finally had a sufficient wake up call.
The problem for me was, I couldn't manage that decision. I could decide all I wanted, but until I became willing (through desperation) to follow that decision with action, nothing much changed for me. That mental obsession was there, and the new found joy of short term sobriety wore off. Life started sucking and a drink started making sense.
AA's Big Book talks about alcoholics repeating that cycle over and over again. And unless I could experience an entire psychic change like it talks about, I was doomed to keep repeating it. That was exactly my experience. Over and over.
When I couldn't go on like that, when I could no longer believe the lie, when I was hopeless, I got willing to take the necessary actions to have that psychic change.
I haven't had a drink since then, and my life has been fulfilled beyond my expectations.