BRIDAL PICS.

I don't know what part of pakistan you have lived in, but it's clearly not like that in many areas. I have been to plenty of parties where couples were dancing, hugging, and all sorts of public displays of affection when they aren't married or even seriously committed. It's not uncommon at all, especially not in karachi atleast. There are all different kinds of people here, pakistani culture isn't just "one".
Just flip through local pakistani tv channels and you'll see plenty of non-mehrams getting up close.