I’ve had a similar experience and quit caffeine 90 days ago after reading the book Caffeine Blues. I recently started reintroducing stimulants (not caffeine, but nicotine gum) to try to get more work done. I’m depressed again, tanking my productivity, not to mention irritable to the point of alienating close friends.
My parents actually got me addicted to caffeine on purpose when I was a kid to “make me smarter.” But I’d say noone knows caffeine is terrible for kids, given that soda (and mountain dew specifically) is equivalent to espresso for kids. Not to mention serving sizes increasing — 20 oz sodas, 16 oz coffees (3x 5oz cups).
I’ve been severely depressed most of the last three years, and it all started when I upped my caffeine intake from two cups to five cups a day to cope with a work schedule that had me working 11–9pm Thursdays and 7–4pm Fridays.