Well, I went 48 hours without coffee. I probably could have gone longer, but I had to wait half an hour for a bus and there happened to be a Starbucks right there... and i had started to feel just a hint of a headache... And then later, I had to wait for a train and there was that same Starbucks, plus now I had my receipt from earlier which meant I could get another coffee for a much reduced price. My head is buzzing a little with the caffeine now. I probably won't sleep early tonight!
I guess the reason I fail to give up coffee for very long, besides being addicted to it, is that i'm not really convinced my health/life would be better without it. It brings me such joy! Surely it must be healthier for me to limit caffeine, but the only immediately perceivable trouble with coffee is that it affects my sleep if I have too much of it.
Still, I'm going to go back to green tea tomorrow morning. Maybe I can make it another 48 hours.