As a similar "addict" who quit caffeine almost cold-turkey last year, I have to say, the withdrawl symptoms are very real. But they also fade as days pass.
Attempt quitting when you can afford to not be at 100% for a few days at a time.
Cut it out cold turkey. No waning off. Nothing. Just no more caffeine.
Day 1 goes alright. Day 2 is a little worse. You'll wish you were dead on day 3-5. But day 6 feels better. Day 7 even better. And slowly, by day 30, you're off.
This worked for me. YMMV. and I believe it's because I consumed zero cups of coffee in this entire time.
Source: ~1 year caffeine free.