Agreed, went caffeine-free almost 3 years ago and feel so much better. Had initial brain fog, and like you described some pretty debilitating headaches and migraines from the caffeine withdrawal, but it passed after a couple weeks.

If you're interested, I found a not-quite-coffee alternative that seems to satisfy my craving. It's a dandelion root substitute, the brand I drink is Dandy Blend. More like instant coffee than a good ground bean coffee but it does the job.