Wow, seren, I'm sorry that you have such a rotten person for a "father". Like you, I wouldn't give him another moment of my time.
I actually had grandparents who were cruel to my mom and her sister and treated their kids (my 2 cousins, and myself and my brother) like shit our entire lives. For example, when their "golden" grandkids were visiting, they could open the refrigerator and get whatever they wanted, and grandma wouldn't bat an eyelash. In fact, she encouraged it... "Whatever you want, you know where the fridge is" with a big smile. If we "black sheep" grandkids even dared to ask for a drink, we got a dirty look and "There's water in the sink". Many times I invited them to come and see me sing, tickets were provided free of charge and we would have picked them up and brought them home...they always had some excuse not to go. When my grandfather was in the hospital having bypass surgery, he kept bragging about how "Your cousin so-and-so got straight A's this year!" but always commented on how much I needed to lose weight (I was fucking 10 years old!!).
When grandma died, I felt kind of relieved that she was gone. I cried, but only because of the fact that she was such a fucking BITCH that she never let us get close to her and there was no reason for it whatsoever. I was there when she kicked, but I honestly just wanted to make sure she was really gone. She did tell me she loved me the night she died (I was staying overnight at the hospital with my mom watching over her), but I ignored it and rolled her over to position her and prevent bedsores. I was completely anguished when she died simply because she died without me knowing WHY she treated me the way she did. I got no answers. And that is what hurt. I think I did all that I did for her when she was dying simply because I was hoping she'd give me an answer and regret that she treated me the way she did...like maybe she'd realize that I'm a good person and she fucked up.
Before grandpa died, he had been in a nursing home temporarily. I hadn't seen him in about 5 or 6 years...in that time I had children and had been divorced. You know what he said to me?? More counsel on my weight, and telling me that I need to set the example for my kids so they wouldn't be fat like me. Oh and tsk-tsking me because I got divorced. "When you get married, it's FOR LIFE! You're just like your aunts, getting divorced and breaking up the family". The last day I saw him, I turned to the side and he laughed and said "Gee, do you have another one in there?" and I just turned around and looked him in the eyes and said "NO, I'm just fucking FAT or haven't you figured that out by now??". The next day he had a major heart attack and I refused to go see him in the hospital. He died the following day. I didn't shed a tear for the bastard.
Some people aren't worth helping. Some aren't worth giving your time to in any capacity. Seems like your father is one of them. So let him wallow in his fear and misery. YOU be happy and, in my opinion, you should just forget he even exists. Let him die alone, that's the fate he MADE for himself.