Great letter, and I know how you feel.

My Dad was a machinist, a guy who was good with his hands, and could figure out most any issue by taking a practical approach. I wasn't like that, and for years I would call Dad before undertaking any project, and every time I hit a stumbling block I would call again. After he died, I still said to myself "I've got to call Dad about this" before the realization would hit me.
Eventually, I asked myself "What would he have said about that?", and to my surprise the answer was usually there. I guess I found the part of me that is my Dad, and I still turn things over to that part when I'm baffled by something. In that way, he's still here with me.
He was no saint, and I see the negative attributes in me as well, and I am working on fixing those as well.
Yes, the painful part will eventually fade for you as it has for me, I think. In one way or another, your dad, and mine, goes on, and there's peace in that.