A Bad Apple in the Big Apple??

On days like today, I must admit I really don't understand people and the motivation to have dislike towards another.  I have had people who would not prefer to have me as their best friends', but I have never experienced this intensity of "dislike" until I moved to NYC. Why do people wish bad on fellow human beings?  What motivates a person to put me down, to make me feel so crappy inside?  Is it jealously?  Is it insecurity?  Does this person feel threatened in some way?  I ask myself these questions everyday.  On the flip side, I also witness the greatest acts of good in this great city.  On my way home from work today, I was blessed to witness a stranger offering another stranger help in the middle of a busy bus terminal.  This made me smile deep inside.  Why is it the negative things that happen in my life seem so large?  Why does the bad shadow the good?   I would like to say that my perception only comes from the good that I experience in my new life here, however, my feelings tell me different.  Will I allow my perception of the Big Apple to be swayed by the Bad Apple or the Good Apple?