Why is alcholism or drug addiction called a disease when in fact it’s a choice?

I’m a recovering alchy & attend drug/alchol classes 4 nites a week, but I’m told as well as the meth heads attending we suffer from a disease of addiction. Why say it’s a disease? NOBODY forced the bottle down my throat nor the crack pipe in anyones face either.
See problem is I attend meetings & recovery groups 4 days a week, The facilitators & counselors all say addiction is a disease. I belive it’s a choice like I said nobody forced anybody to use. Is it just an excuse not too take responsibility for your actions? And by the wikipedia isn’t a reliable source.