maybe your mom doesn<t want you to end up supporting her big family all your life. i think she thinks the way she does because it is for hte most part true that any guy or girl from paksitani is marrying outside to get out nd help their family better their life situation unless they are ameer themselves.
but on the other hand, how does your mother know that you won<t get a crazy girl from usa. their also lots of stories of them like for example sending the guys to jail and fighting and divorcing and taking half of what the guy own etc etc.
if you are really into the girl tell your mom there is always a give and take to everything. and if you really like the girl if you love her then so what if you help the poor girls family out. isn<t love about giving. isn<t ti about being unselfish.
besides it is not everyday that you click wiht someone and feel somthing special. and you could give your mom a time frame and tell her since she is so skepticle she can try tot find soemone for you in usa that you will feel something speical for. i bet she won<t be able tot do it.
don<t listne to skeptical negative thinking too much even if it comes from someone as close ot you like your mom. if you do u might make yourself mehroom(devoid) of hapiness in your life and regret taking this type of advice.