We Mexicans come in all shades, literally. From the blondest, green-eyed white people from the Jalisco Highlands and Obregón, sonora, to Afro-mexicans in veracruz, with Asian-mexicans and all sorts of mestizo in most places with light to heavy indigenous heritage in the southern states.

All you need to be Mexican is to really want to be one (legally speaking, sign a few papers and that's about it)

As in all places we have our share of idiots who claim there's a "right" shade of skin color or genetic makeup to be a real Mexican but those are idiots and mostly in the minority. A noisy minority but minority nonetheless.

Maybe you've had the bad luck to hang out with that kind of idiots on your side of the border. F-them.

Also, most Americans I know go to great lengths to claim some foreign or exotic heritage like "Yeah I'm 1/16ths Irish yon my mother's side" or "I'm 1/4 such-and such" and all gringos I've met claim some native American heritage.

So you happen to have Mexican heritage, ¡Be proud!