Some people get out of opioid addictions cold turkey, by just not consuming more opioids, enduring the withdrawal symptoms, and then getting rid of the chemical dependency.

Since we know this phenomenon is real, this means that, even with a chemical dependency, people choose whether to take the drug or not. So, by your logic, they are not really addicted, they can just choose to stop at any time, they're just silly and weak people, right?

Of course this is reductive and simplistic. Ultimately your choices are a computation that your entire nervous system makes, and urges and cravings are a component of that, just like rational processes are. Different people's nervous systems weigh these factors differently, and have more or less powerful cravings and urges to begin with. It's absurd to think that your rational thinking can overwrite anything in any condition, and it's absurd to think that all people experience these thinks to the same extent.