What is difference between atheism and nihilism?

Nihilism I think is true, and I am an atheist, it just has a bad public image because we want to believe theres some purpose to life other than the one we collectively assign to it. It's not good enough unless if some supernatural being assigns you a purpose? However, atheists DO NOT have to be Nihilists. For instance, Buddhists might not believe in gods but they feel there is some purpose to life. My problem is they arrive at that purpose using some religious methods, ie. square 1, no evidence.