They call it a disease, because it is genetic. You can inherit a tendency towards alcoholism.
Like diabetes - if you inherited the gene, but you'd never eaten a chocolate in your life you would still have the diseased gene.
I agree to a point - it makes it sound like it is not the responsibility of the 'victim'. But again, like diabetes, if you know you have a tendency towards it and you DON'T make moves to avoid it becoming a problem, you are essentially condemning yourself to an early death.
As I say, it is a scientific definitive term, to help doctors differentiate between people who are emotionally/psychologically dependant and people who are genetically prone towards addiction, iyswim?
But its been hijacked by people who don't want to take responsibility for their own problems.
Just FYI - it might be worth keeping an eye out among your siblings/children/nephews and nieces for signs of an addictive personality because it's a lot easier to deal with "I tend to go OTT with things, I should make sure I am moderate in my consumption of all things" than it is to deal with advanced alcoholism.