I didn't know about this saying, but it is true that after some time it becomes a habit, I can confirm that.
Sugar is a huge factor and so many can't even see it, or don't want to admit it. It was two years ago, when I started a no sugar challenge. Initially I said 30 days, then went on for 2 months. It can definitely be done, but once you are done with it, you can easily go back to your old habits, like eating something sweet after lunch, or dinner.
15 candies is crazy, no offense. Even half is crazy to me 😮 and it indicates addiction. If you can beat it, you're a winner. I'm eating chocolate with 80% cocoa, 1 small piece (5g), which is not sweet at all and I can guarantee you, after you eat a little piece, you don't want more.
Congrats on your journey.