Shy,
If he has taken on the resposibility of filling the shoes as your dad, damn right you can confront him, I have five kids and 7 grandbabies.My oldest is just a stepdaughter, but she is still my baby girl, always has been, and always will be, I treat her as my own, even my real kids look up to her as a big sis.
I know how you feel, I have always worked on the road so was not always there for my kids like I should have been, but they always knew what was going on with me, he is your dad, talk to him honey, let him know your feelings, trust your heart and put a little trust in his.