With south Asians particularly pakistani Muslims families, they seem to have their wires crossed, they mix culture and religion up and will class culture to be part of their religion e.g. Pakistani culture will involve a Pakistani girl strictly marrying a Pakistani and the family will also see this as a religious thing so it backs up their arguments, whereas in Islam a girl or guy can marry someone from any background as long as the person is a muslim.
Also they're cultural ideologies are very backwards even till this date, these are the faults in the culture which makes life harder for you.
I hope that things get better for you xx