Personally, I think it is a disease. A horrible one...
Some disease never goes away, but "medicine" can put it in check. For the addict/alcoholic, it is recovery...
My friend's father is schizophrenic. When he is not on his medication, he lies, cheats, steals, says sexually inappropriate things to everyone including his daughters, and becomes violent...He become malicious. When he is medicated properly, he doesn't have the symptoms. He is probably then one of the greatest guys I know. However, there are periods of time that he BELIEVES he is not sick, so he comes off the medication or says he doesn't need it. The disease takes over...the same thing with the A. Sometimes they never see what is wrong with them or feel that they can keep the problem in check on their own. They come off of the medicine that is recovery or say they don't need it.
We, as the second party, have a choice to decide whether or not we are going to live and accept their decision. I personally cannot live with my AH anymore because of his choices. That is my choice. My friend's mother chose to leave also because of his choices.
It is easy to question in both cases whether the person is a weak, spiteful person or if that is the disease.