I feel that there are 2 broad types of vietnamese gals that we are discussing about here:
(1) She may be a working gal, normal gal or even highly educated vietnamese gal. But you are SERIOUS about her and you are thinking of marrying her or you have already married her. You treasure her and see the future for the both of you and your love.
(2) She is a working gal, normal gal or even highly educated vietnamese gal. But you are playing with her, taking her as SEX OBJECT and keeping her as a pet to pass time. You do not see yourself having a future with her and neither are you willing to scarifice anything for her. You should be married or maybe having serious commitments elsewhere
If you belong to Cat (2), then you can do whatever to her because she doesn't matter to you and if you lose her, next better one will come along. But if you belong to Cat (1), there's no way that you can tell her not to control you.