I have thought about this long and hard throughout my whole life as, no doubt, everyone in this world has. Thus I have come to two inevitable conclusions of my own, both accepted by many people:
We are created by a higher being for a purpose, and subconciously we fulfill that purpose whilst living a life of meaningless situations and circumstances that inevitably lead to that concluding purpose. I have ruled this out because this conclusion would mean that our lives are truely meaningless to ourselves and only serve this "being" that may or may not exist.
My second conlusion is that we create ourselves out of an infinite emptiness of which we are bored. We created all of this world around us as a means to entertain ourselves in our absolute emptiness. Therefore, it is our only purpose to enjoy ourselves and indulge in the pains, loves, joys, sorrows, and all instinctive emotions and triggers our subconcious mind has created for us in this beautiful world. I accept this conclusion because it places me as my own creator and a slave to myself. Indeed, if this is true, when this world ends, a complete new world shall begin with all sorts of pleasures and pains!