I do not consider addiction a disease by any definition of the word in regard to how it is used today. To say I have a disease that is progressive and comparable to such diseases as cancer, Parkinson's disease, ALS, heart disease, diabetes, etc. is absolutely preposterous. These diseases are progressive and physically manifest themselves within the body. I will not go up to a cancer patient and say "I have a disease as well" when I can give up the drugs and alcohol at any given point. If I can't? There's plenty of help out there today to get me clean.
Taken from the Big Book itself (which has never lied to me), it explains that "...when the spiritual malady is overcome, we straighten out mentally and physically." I consider addiction (any addiction: drugs, alcohol, sex, whatever the hell people want to call addictions) to be a spiritual disease. Spiritual is a hard word to define, but for me it was going against everything my inner being was. Doing everything against my core beliefs. Twisting and turning my beliefs and actions so much that it made a rat's nest out of my mind. In turn, I used drugs and alcohol to cope and that made me even more mentally insane along with physically sick most of the time. It wasn't going to take me to my death: it could've, but I reached out for help. The mental obsession was broken. Forty-one days away from a year of sobriety, I will tell you that the problem centers in the mind.
Do not discount the mind. It is the most powerful thing known to man in the universe. To heal, start spiritually and watch as you develop healthy mental and physical practices.
Just my two cents.