As a former athiest, I will tell you what I had found. I assume you are highly intelligent for chooseing athiesm and not a doctrine presented. I looked to philosophy. An great athiest, Jean-Paul Sartre. Existentialism is Humanism.
[link to www.marxists.org
"But there is another sense of the word, of which the fundamental meaning is this: Man is all the time outside of himself: it is in projecting and losing himself beyond himself that he makes man to exist; and, on the other hand, it is by pursuing transcendent aims that he himself is able to exist. Since man is thus self-surpassing, and can grasp objects only in relation to his self-surpassing, he is himself the heart and center of his transcendence. There is no other universe except the human universe, the universe of human subjectivity. This relation of transcendence as constitutive of man (not in the sense that God is transcendent, but in the sense of self-surpassing) with subjectivity (in such a sense that man is not shut up in himself but forever present in a human universe) it is this that we call existential humanism. This is humanism, because we remind man that there is no legislator but himself; that he himself, thus abandoned, must decide for himself; also because we show that it is not by turning back upon himself, but always by seeking, beyond himself, an aim which is one of liberation or of some particular realisation, that man can realize himself as truly human.
But this was the beginning.
From there I went to science. Quantums physics. Entaglement, decoherance. Ultimatly I found "God". It is not what people tell you. You wont know untill you put the effort in to find it. But if you feel a force with in, tearing everything down, it is a humbling to seek the truth.
This course took me years to come to the conclussion. I went through horrors of war, and self distruction to understand that the world, and everything in it is designed to become self aware of the source of you. Nothing else.
Keep seasching, and disrgard everything beyond yourself. Your intuition is your guide. Christians call it the holy ghost, I call it the entagled energy of life interacting with your quantum mind. It all comes from the Sun, and is dispersed through all life, originating from one point beyond time and consciousness.