Earlier quoted context omitted.
That something is addictive doesn't absolve you of accountability; you still got addicted to it, you allowed it to happen, you are still responsible for yourself no matter the biology of how the effects work. With very very few exceptions, people are fat because they eat too much food, it's as simple as that. If you overeat (as an adult), you are to blame, it's not anyone else's fault. I agree with the OP.
So you're saying that it was your choice to have your first bite of sugar, and you could have abstained? This kind of "abstinence-only personal fitness" might work fine for cigarettes, but kinda breaks down when it's stuff you've been fed since you were 5 weeks old and has been injected into most pre-prepared foods in a "sweetness war" that's lasted decades.
Want to break a sugar addiction, stop eating, fast until you've broken all food addictions and shed much of the stored calories, and then build up a better diet when you start eating again.