I have read the whole story and I can relate what you feel becuse I came from a broken family where I grew up with my stepfather. My mother didn't tell me that her present husband is not my real father.
I am confused why?? Where is my biological father? Then one day here is a man who introduced himself that he is my biological father and as I look at him it seems that he is my reflection.
Knowing our story will not keep us in peace there is a side in our heart that we need to know who he/she is.
Since we have our own family now that helps us enlighten our feelings of looking for our emptiness, I hope and pray that you feel better now.