no name change policy

hi,<br> I am booked to travel cape town on 7 of august with my wife. for some reason she cant travel with me.<br> so I decided to take my friend on her place. when I phone for the name change I was informed that it against the airline policy. they are prepare to do exchange for my wife but they cant change the name.<br> please see how can you help me, otherwise I am going to loose money.<br> thks.<br> abid hms jamadar