I'm also a sugar addict, very bad. I think the approach to this really depends on your personality, and what you can do. The first thing I would highly recommend is ditching the soda. I think especially soda causes more sweet cravings - you keep wanting that sugar high. Like pp suggested, maybe switch to juice and wean from there.
Once you get rid of soda, it will be easier to resist sweets, I promise! I noticed once I got rid of the soda, other things like fruit tasted even sweeter to me, and hit that sweet craving. I think the soda is so overly sweet everything else pales in comparison.
I've done white knuckle, no sugar fasts too. It does help, but I can't keep it up long term. I like sugar too much
I try to allow myself a little bit most days, even if it's just some nutella on whole wheat bread, and that helps keep my sugar monster tame.