Learning about wiwille

After 41 years, I finally made contact with my birth parents. After I finally received my pre-adoption birth certificate, my wife did some internet legwork and found their contact information. She reached out to both, who confirmed they are my birth parents. I found them to both be alive and well living in Washington. I've spoken to them both at length and they've provided me with a lot of information. The things I've learned:

1. I'm mostly Irish, which would explain my fascination for stout beer.
2. I have two half sisters, both of whom are, as my friends have put it, hot. I really got screwed in the looks department.
3. My birth father's wife had no idea of my existence, until I reached out to him. He then told her about me, and she thankfully was excited.
4. On my birth father's side, only him and his wife know I exist.
5. On my birth mother's side, only her and her husband know I exist.

I've been keeping this from my family to not hurt anyone's feelings. They've been good parents and I don't want them to ever think I would refer to anyone else as mom or dad, but I feel a tremendous amount of guilt because of it for reasons to numerous to detail.