I've never been able to do the forever statement (though I've read & appreciated Rational Recovery & AVRT techniques). Nor has the "one day at a time" been sufficient for me.
My personal merging of the two sounds like this "I'm staying sober during Mardi Gras season - no matter what - then I'll reconsider." Or "I'll stay sober until November, then I'll reconsider."
The good thing about this odd method is that I individualize it to my life. Most often, by the time I get to Lent or November, I'm so solid in my life that it is a no-brainer to stick with my sobriety commitment. Then I add on another section - "ok, I'll stay sober until next Mardi Gras...or next November..." The hard part is that instead of getting a lifetime of freedom, I have awkward reconsiderations every few months (& have - once or twice, chose drinking & regretted that decision & returned to sobriety).
This is not a functional method I'm suggesting. But - so far - those are the longest commitments I've been able to confidently speak & shoulder. They are getting me through. They are short-term, but add up. They require lots of re-evaluations. They mean I've done a ridiculous amount of step work & have a giant pouch of AA chips, dating back to 1986.
I realize this is not a PC or ideally inspiring post, but I decided to post it just to show that while some of us have brains that resist sobriety commitments, we can actually trick ourselves into being sober for - well - most of our adult lives. I'm still scared to say "forever" but I've sort of committed to "forever" regardless. Extra work, but it was the only way I could throw myself in...
The "just for today" was too small & the "forever" was too big. I had to trick myself...