You are 44 Steve? How many more years are you prepared to waste thinking and worrying about her? The rest of your life? Do you not think you deserve some happiness yourself?
My XH is just like you describe your dad. The raging outbursts we had to live with was terrible and I saw what it did to my son's self-esteem. The feeling that he is not lovable and therefor seeking out relationships to prove it. It is so sad. I hope you will be able to get past this and realise just how much you are worth and how much more you deserve.