Paul, I've only just found this thread. I wanted to add my condolences once more, and tell you how brave I think you are for putting yourself through all that out of respect for your father. Some of the things that were said to you were truly shocking, and you did really well to bite your tongue. I think I would have struggled because I seem to get wound up quite easily at times, one of my many flaws.
I was 21 when my Mum died, and one of the things I really hated was when brothers/sisters who had already lost either of their parents said "I know how you feel". NOBODY knows how you feel when you lose your mother or father, since nobody has had the relationship/experiences that you have had, or knew the person in the way that you did. The worst was when one brother who didn't even know me, but who found out about my loss in conversation, told me that he "knew" how I felt. The brother in question had a wife and children, and the parent who he had lost had died after seeing both his wedding and the birth of his children. My mum never witnessed my wedding (never even met my wife) and will never see her grandchildren. How could he possibly know how I felt? I somehow managed to bite my lip at the time, not sure how. I wish people would engage their brain cells before speaking to somebody who has just been bereaved of someone who is a major part of their lives. It's the worst possible time to say something careless and insensitive. You did so well.