Interesting question. If there was no God, there would be no purpose to life or point to living. If you read this forum thread, people were asked this very question: What's the point of living if you're going to die anyway? How did people respond? Some said the point of life is simply to live/have fun/enjoy every moment. Others said it is to procreate. One person said life is an illusion and left it at that. As you can see, there is a lot of confusion and speculation. This is one of the biggest problems with atheism: It cannot give you a satisfactory answer to the meaning of life. If you really believe that there is no God, then you must believe that you simply cease to exist. Your body is buried in the ground. This is how Matt Slick of CARM.org puts it:
If atheism is true: The universe has laws. These laws cannot be violated. Life is a product of these laws and can only exists in harmony with those laws and is governed by them. Therefore, human thought, feelings, etc., are programmed responses to stimuli and the atheist cannot legitimately claim to have meaning in life.
Mankind must find something outside of his own limited knowledge and interpretations on which to base his life if he wants any security at all. Science cannot define meaning in life, nor was it meant to. And it is meaning -- purpose -- that must be found for a man to be satisfied and have a direction in his life.
God created us to live forever through his Son Jesus. He crafted us with a purpose in this life and in the next. Even if the world ends today, Christ-followers have nothing to worry about. Jesus will come in his glory; He will gather us and we will live with him forever (Matthew 24).
I recommend you take a moment and read the first 7 chapters of Rick Warren's Purpose-Driven Life. I think it will help your thinking in this matter. Finally, ask yourself: What are you living for? What is the point of living? And consider what C.S. Lewis once said, "All that is not eternal, is eternally useless." God and his purposes are eternal. Live for Him.
[Answered by Pastor HM, who is glad I live for God's purpose - and not my own]