I take a different approach in this respect. I entirely deny the actual existence of any abstracts at all. Good, evil, right, wrong, justice-- they're all imaginary, but they are also the inevitable result of the way our minds work. The question, in my mind, is of the degree to which we want to pretend that these things are absolute, for the sake of our happiness.
Now, god, I think, is a seperate emotion from the ones that govern morality. Ethics are about the people around us, while stark spirituality is profoundly personal. Spirituality is the same thing as our sense of beauty. A figment of our perceptions, perhaps, but it nevertheless has a very strong effect on us, and thus cannot be written off as simply a "lie" or a "fairy tale." I do not believe in god, an afterlife, a soul, or in any metaphysical world whatsoever, but the thoughts and feelings I experience when I listen to a Gregorian chant or to Handel's "Messiah" are real, and they say something about the nature of humanity.