I have no idea how my biological parents looks alike. But what's wrong with looking like your family? As long people loves their family members and have a good relationship to them, it seems fine for me. My biological parents are probably short, skinny and have a Asian appearance. I would rather look like my biological dad than looking female probably. I have no idea how he looks alike, but he looks probably similar to other Chinese people.
I understand you don't want to be mixed up with another person and you want to be yourself. But nobody can refuse you being yourself and most people understand you are difference than your family even you looks like them.