The term 'falling in love' is apparently mainly used in Western society to describe the process of moving from a feeling of neutrality towards a person to one of love. The use of the term "fall" implies that the process is in some way inevitable, uncontrollable, risky, and irreversible.
So 'falling in love'... its supposed to hurt! and we're fairly warned in the title! If it doesn't hurt then you probably never fell in the first place! <3