Why do we exist

Why do we exist? it was a question that haunted me for so many years. Since i was teenager, i was bother with this question. My friend always said that live the life while you are still young, and don't bother with such question,coz you're not gonna live young twice. Well, if your life is always in a good condition, i mean really reallly good, with lot of money and lot of friends to be happy perhaps you won't asking such questions coz always being occupied with such pleasure. I don't say that my life wasn't good enough, during my teenage life, i always went with my friends, went after pretty girls, :P. However, there are no parties that never ends, i felt why those good things always end so fast and end up with bored feeling, everything means nothing.
Those pretty girls were not so pretty anymore after quite sometimes, and those cheerfull friends were gone. There was all me, and nothing else there.
Then with boring minds and scrambled emotions, i saw nothingness in life, so unusefull being. The only thing that keep me sane during that time was the faith that any of us have a purpose, and with emotion and sanity left i decided to search the answer rather than being torn with such feeling. The search led me to meet some people who taught me well in contemplation and give me lots of information about existence, but yet the answer was never been reached. However, during a series of contemplation i finally saw a glimpse of light of answer. It seems that life and existence is intertwined in a story that we call destiny, in other world life is a story in which can't be understand before the story completed.