I'm going to echo both of dollydo's posts. Alcoholism is a progressive disease. It will only get worse with time. My AM used to be fairly pleasant when she was sober, but that was a good 20-odd years ago, so I don't remember much of those days. The majority of my life she's been a bitter, angry alcoholic, with or without alcohol in her.
Replace your father with my grandmother and you have a predicament that I took onto my own shoulders for a long time. It finally took me going No Contact after an episode involving my children to make me realize that the only people I can save are myself and my kids. I can't get my grandmother out of that house and that situation, no matter how hard I may try. You can't control another person. I recommend you work on your own recovery in order to achieve peace and serenity in your own life, while becoming accepting of your father's decision. You can't change it, so you might as well accept it.