In someparts of India ,especially in Tamil nadu ,people eat the extremely bitter (margosa ) flower on New Years Eve. There is another celebration at the end of the year called Pongal ,on the day the sun touches the tropic of Capricorn .On this day ,people traditionally chew sugarcane. There is a great deal of symbolism in all Hindu celebrations .In these two particular examples ,chewing the bitter neem flower symbolizes the acceptance of lifes bitter experience from the very first day of life .life involves many hardships & msifortunes.We should learn to accept & even welcome them wholeheartedly,to be patient ,enthusiatistic and optimistic never allowing ourselves to mentally weak or disappointed .Only then can we progress towards the real goal of life-the sweet bliss and joy of immortality .this is symbolized by eating sugarcane at the end of the year.
Source : Awaken Children