Everybody's physiology is different, but I drank a full pot of coffee every day, for about 15 years.
After Getting Older™, I was noticing more and more effects that I didn't like, so I made the decision to (mostly) detox off caffeine using decaf beans. Cold turkey would have destroyed me. I went with the following schedule:
* Week 1: 75% caffeinated/25% decaf beans
* Week 2: 50% caf/50% decaf
* Week 3: 25% caf/75% decaf
* Week 4: 100% decaf
At week 4, I entered a full failure mode I hadn't yet experienced, namely migraines that were untouchable by OTC medications. Only caffeine helped. I tried to get through the week to "be done" with the weening but couldn't. So...
* Week 5: back up to 25% caf/75% decaf!
* Weeks 6-12: decreasing caffeine by half each week (to the point I was measuring beans using my home scale).
After week 12, I was able to go without caffeine, and now I drink 1 cup of coffee and, if I'm feeling wild, I'll occasionally get an espresso.
My physiological dependence on caffeine was no joke, but I feel a heck of a lot less anxious and jittery after cutting it down to where I'm now at.