I've been a bit of a yo-yo quitter in the past (trying not to be) and the way I see it is that you've got two lots of quit-times under your belt, three and four months, which is already pretty tremendous. Think of all the repairing your body will have done during those periods. And remember that having already done it twice, you *know* you can do it. That fear of stepping into the unknown should be absent, or at least reduced. You've already done half the work. Go you!
As for staying stopped: I'm still working on that myself. Ahem. What I do know is that there's no one-size-fits-all answer, and you (as in, one) need to work out what works for you. If the thought of never drinking again fills you with fear and that fear in turn makes you want to drink, then use the one-day-at-a-time method; if that way seems too ambiguous then commit to something more permanent.
Either way, and whatever method you self-prescribe, there will come a time when you have that amnesia about why you stopped in the first place. Let me know how you deal with that one...