This alcoholic was certainly a liar. I don't know if it's a trait common to all alcoholics - though AA tells me it is - but the desire to meet what we think are other people's expectations of us is in constant conflict with the practising of our addiction. We don't want to disappoint, but we constantly do. So we lie to ourselves to pretend it's all ok. And by extension we lie to those around us. And we feel guilty, and ashamed, and we can't stand it so we continue to use.
I know that there are forums here for the family of people with addictions. I hope they are able to give you what you need.
Best wishes
Paul