I'm very sorry to hear that Del, and damn sorry for your personal loss. Having lived through this myself, I can tell you that the sorrow will dull, but your dad will never be far from your thoughts.
Hang in there buddy, your dad would want you to be strong and make him proud.
Agreed.
My dad died at 65 some 34 years ago when I was in my 20's. While details have faded over time I still think of him relatively often and feel he's still watching over me.
The odd thing was he died relatively quickly of health issues (about 5-6 months after onset of conditions) and I had no emotional reaction to his passing whatsoever until the day of the funeral when I broke down sobbing uncontrollably. Until then I was thinking I must be some cold SOB. In the end, not so much. I was just good at internalizing. Each person handles these things differently so however you deal with it just let it happen naturally and it will get better.
Finally, people have an amazing ability to remember the good things and forget the bad things over time and your memories of your father will be fond memories for the most part.