Yes!
I have a sister who refuses to hear about our father's alcoholism (he died from cirrhosis of the liver when we were both under 10 years old). She still thinks of him as wonderful, loving "Daddy." I remember him as a sick, abusive, unpredictable, scary monster.
She has never gotten into any kind of recovery program, and is still very much the untreated ACOA. We aren't very close; we never were. We don't communicate much.