How do I start? Gradual or cold turkey?

I eat pretty healthfully, with the big exception of sugar. I know it's time to start changing my ways but I don't know if I can square with never eating chocolate again. Plus my mom just got cancer and I've been an emotional mess, so not using it as a crutch is gonna be tough.

That said, I know myself and having none is easier than keeping track of exactly how much I permit myself. Has anyone had success with gradually reducing sugar? Or is cold turkey the way to go? Or maybe one treat per week? I really want a plan I can stick with for the long haul. Any advice or experiences to share?