Therapist post of the day! Answering the age old question of how is addiction a disease and not just a choice?

Had a discussion earlier about this and it's been heavily on my mind since. Many debate this and yes semantics get too much in the way at times. But there is importance in understanding how and why addiction is a disease and not JUST about choices. 
Let me explain it the best way I can. Let’s use heart disease. I think all can agree heart disease is a disease. It is related to a dysfunction of the heart, an organ in the body. One can either be born with this or develop it over time. There is a varying spectrum in the seriousness of different people’s heart disease. One person can have a slight dysfunction and require simple lifestyle changes to treat it, such as exercise and healthy diet. Other more serious versions require medication and/or surgery as well as lifestyle changes. Unfortunately there are those with the slighter version that refuse to make those changes. This in turn causes worse symptoms of the disease and could potentially lead to death. And sometimes those with more serious forms of the disease can continue treatment and make lifestyle changes and live a long happy life. Now how does this relate to addiction? Addiction is a disease. It is a disease of the brain, an organ in the body. Individuals with this disease have altered chemical makeup and different brain patterns of someone who does not have an addiction. These patterns can be from birth, passed down from parents, or it can be created by bad lifestyle choices. In the end the brain has a dysfunction that alters the person brain, again an organ in the body. Now like the person with heart disease a person with an addiction can have varying levels of severity of this disease. One individual can have this dysfunction and choose to seek treatment and make lifestyle choices to prevent further decline. Some individuals with a severe form can make the choice but they require very intense treatment, such as a medical detox to prevent physical symptoms, which have been known to cause death. Some of these symptoms include seizures and severe pain. They have to continue to stay the course of treatment the remainder of their life. These individuals cannot partake in substances without fear of falling back into the same behaviors or triggering the dysfunction in the brain, once again. Some individuals are less affected by this dysfunction and are able to make lifestyle choices to remove themselves completely from this addictive behavior. To them it is much easier because: 1, the dysfunction has not been made more severe by long term usage, or 2. they were not born with the severe form of this dysfunction. In saying all of this, as with any disease there is an element to choose to treat or not to treat. Some are deadly and even with treatment it may do no good. Addiction can be treated, and one must choose to treat it. Unfortunately many choose altered brain chemicals over their families and living in general. Many fear being sober and what that may mean for their life. But it is indeed a disease. You still have a right to be angry with someone choosing not to treat it, just as you can get angry at someone who chooses not to take their insulin for their diabetes.
Here is a great website with more info. on addiction.