Gave friend to money half of it returned now not returning remaining

Hi There, I gave X amount to a friend via bank transfer. Within month the friend returned the half of the money via bank transfer and requested if rest she can give me half of the amount later , to which i obliged. Money was transferred in Sep 2012 and half was given back in December 2012. I left the country in Jan 2013 and came back in Dec .2016. The friend also left the country in year 2014 and is in US. During this period i kept sending mail, requesting for payment , to which she said she is trying to arrange the money , but 4 years are gone, and she still gives some excuses. All communication are on mail. I know the family. What chances i have here to get the money back via legal way. Thanks in Anticipation