What is so wrong with there being no purpose? It seems alot of theists seem to need God to be real in order for there to be purpose and meaning in their lives, but I think “Why do you need purpose?”. You don’t need purpose to enjoy life, or maybe you can just assign your own personal meanings, give life your own purpose, as most people do.
If the purpose of your life is to be happy, then go on, go and be happy. You can do that without God. Live life your way, for then, you have freedom. Freedom of purpose, or from purpose. Whatever floats your boat.