I have been in a very similar place as you are now with my Dad and his drinking, I am worried about his health etc too but he is too caught up in himself to listen. However, every now and then he takes stuff I have said to heart and listens, it could be days or even weeks after and he changes his drinking habits. This means that deep down all along even though he was rowing with me he understands why I am doing what I am doing. It hurts Dads when their little girls stand up to them, and they react badly but they do take some of it in.
However, one thing I will tell you is that I worried so much about my Dad that I got very sick and ended up in counselling- I was "diagnosed" as co-dependent which means that I worry so much about others and try to control their bad habits that I don't look after myself. I have to try really hard to keep this in check. I'm not diagnosing you by any means, just sharing a cautionary tale.