Many theists like to classify us atheists as unhappy people with no purpose in life; when in reality, nothing could be further from the truth. I believe that everything you need to be happy in this life is already present within you and you don't need a god to give your life purpose. I have been an atheist for the past 15 years and I actually feel better than when I was a practicing Christian.
Many theists including myself when I was one, speak of the liberation one feels when they commit their life to Christ and apply his laws and precepts to their lives. But the moment I denounced my beliefs in Christianity I actually felt like a great weight had been pulled off of my shoulders. I admit I was an extreme Pentecostal evangelist who took the bible literally and believed every single word that was written between its covers. But as such I was always worried about my standing with God, I always wondered if I was living up to his expectations.
I worried about death and hell constantly and wondered when he would come to rescue us evil sinners from ourselves. Life without God these past 15 years has been incredibly fulfilling, I now have control over my life and I live for me and what makes me happy. What most people don't realize is that when you commit your life to Christ you are no longer living for you but for Christ. You turn over your will to his will hence the line in the Lords prayer: 'Thy will be done'.
Life is so much more meaningful when you live it for you, and you take full advantage of all the things life has to offer in the here and now. Instead of wasting your life on some pipe dream of perfection and bliss in the hereafter, you should be making your own little slice of paradise on Earth doing what makes you happy. You don't need a God to figure that out.