Ditto, 100% same story. I kinda knew I had ADHD and was able to investigate some childhood stuff that suddenly made more sense, but I waited until I had a crisis that was compromising my ability to function at work before finally talking to a shrink. Wish I'd done so a lot sooner.

I can start/stop, take drug holidays, etc. with amphetamine (adderall in my case) at will with no ill effects. Caffeine on the other hard, is brutally unpleasant to miss a day of. Been on the same dose of adderall for a few years now. I was able to reduce my caffeine intake significantly after starting adderall.