What's wrong with my parents?

I came home from hostel after 2 months! Today in morning I am just talking normally to my mother about my friends and all and suddenly she asks me "ladkiyan bhi dost hongi tumhari to?" I said yes then she said very sarcastically "zyda dosti to nhi ho rahi ladkiyon se" Like why is this so uncommon for our parents that their boy have female friends or their girl have male friends... Can't the boys and girls just be as normal friends for our parents? Why??