Board Thread:Spoilers!/@comment-23906605-20131017110136/@comment-22525977-20131029060908

Emma was, at the time Neal left her, 17 or 18 depending on when her birthday was in relation to Henry's and pretty idealistic considering her upbringing. She's going to be a lot more open to her boyfriend whom she trusts and loves telling her that, hey, magic exists than some random stranger she barely knows and whom she's pretty suspicious of telling some crackpot story about how she's the savior, ten years later after she's grown some proper cynicism.

Neal doesn't have to tell her she's the daughter of Snow White, nor does he have to tell her everything all at once. Ten years is a  long  time, and he could let her in on it gradually.

Also Emma is not a magical creature, she's a human being.