The typical atheist rebels against God as a teenager rebels against his parents. When his own desires or standards are not fulfilled in the way that he sees fit, he, in revolt, storms out of the house in denial of the Word of God and in scrutiny of a great deal of those who stand by the Word of God. The epithet 'Heavenly Father' is a grand reflection, a relation to that of human nature.
Of all the major religions, or lack thereof, the atheist's is one of the best pretenders: his foundation for all existences, as well as moral behaviors for the permanent good of mankind, begins at science but ends at himself, the Napoleon complex of both intelligence and imagination. On the other hand the anti-theist wouldn't survive without a deity beyond himself to hunt. He doesn't pretend, he simply nullifies his own position.
Man has 2 common problems with God: the one is that there is evil in the world; the other is that free will is limited. The one, he is charging that the world is too evil; the other is that it is not evil enough.
I suppose that one reason I have always detested religion is its sly tendency to insinuate the idea that the universe is designed with 'you' in mind or, even worse, that there is a divine plan into which one fits whether one knows it or not. This kind of modesty is too arrogant for me.
Religious belief is without reason and without dignity, and its record is near-universally dreadful.