Michael Archer: The reply manager only allows a limited number of characters per response. I will be responding with four replies.
If we take your definition and analyze it against the norm for humans, which is heterosexuality, we see dual standards on your part. 
You could say, “There are people who experience opposite-sex attraction, but do not refer to themselves as "heterosexuals”." They consider themselves people with opposite-sex attraction, or they don’t define themselves this way at all.  (In the past, most heterosexuals never even thought of people as being same-sex attracted. There were so few “known” people like this. Each same-sex attracted person lived as an island and was not known usually, as such, to many.)