When Angry Words are Your Last

Lately, I have been biting my tongue, practically off.
So I will tell a story, 2 weeks before my dad died.  He and I had an argument, that at that moment it seemed gargantuan in proportions.  It was a matter of pride and a question of me and my abilities and who I was, I wish I could say I don't remember what it was about.  But 32 years later, I still remember and it still hurts because these were the last words, we spoke to each other.  It was so hurtful at the time, that I had the opportunity to go see him the weekend before he died and didn't.  In retrospect, the argument was inconsequential in the master plan of living.
So, when I ask for something to be done, I am not doing it to torture you.  I am asking to make our life around here easier and better.  I am sorry, that you see others not doing, but are you!  I am sorry my health is such that I slow down too fast.  Believe me it is frustrating for me.  I just don't understand and I refuse for our last words (because we never know what will happen) to be angry words.  I just need your help!