First, the only way you can be together is to marry her(she can't get visa to US unless your married).
Second, Most families in the Philippines are very traditional compared to our culture.
Lastly, I'd say that her parents might just be concerned that their daughter might get hurt by having high expectations of you marring her.
In the Philippines many women try to marry Americans or Aussies because it is the only way to leave their country for a better life and there are thousands who start these online relations that never end in the man coming to their country and marrying the woman.
On top of all this, if you had daughter, would you want her to leave your country and possibly never or hardly ever seeing her again?
Is this like first hand experience or just a true to life story? You are correct with us being traditional and conservative to a higher degree. Most would not understand this till they get to know our culture but I do believe that being committed and in love will weather all the obstacles of distance and culture. An apple cannot be borne out of an orange, meaning to say if the person is good the family he came from is not too far from how the person is. Women from the Philippines are sweet and caring you just have to look at the right places and find the real ones