Those who disbelieve in God will usually agree that there is no objective meaning to their lives, but deny that therefore there is no meaning at all. Instead, they argue that their lives can be fulfilling and purposeful from the subjective perspectives of themselves and other human beings. Because they find this satisfying, they do not sink into despair and they do not feel that suicide is the best option.
People who cannot be satisfied with personal meaning may not be able to resist such a move; for them, then, suicide would be appealing. Nevertheless, that is not the conclusion typically reached by existential nihilists. For them the objective meaninglessness of life can often be viewed as quite liberating because it frees humans from the demands of tradition which are themselves based upon false assumptions about the binding wills of gods and ancestors.
This is the conclusion that Camus reached in The Myth of Sisyphus. A mythical King of Corinth, Sisyphus was condemned to spend eternity pushing a rock up a mountain, only to have it roll back down to the bottom. Sisyphus had no meaning, no goal that could be reached and it would never end. For Camus, this was a metaphor for life: without God, Heaven and Hell, all we have is a terrible struggle that in the end we are condemned to lose.
Death is not a release from our struggle and a move to another plane of existence but rather a negation of all that we might have accomplished by our efforts. How, then, can we be happy in this knowledge? Camus argued that we can be optimistic in the face of this by refusing to be blinded to the fact that this life is indeed all we have.
Pessimism is only merited if we assume that life must be given meaning from outside our lives, but that assumption should have been dispensed with along with the assumption of God because, without God, there is no position outside our lives to hand down meaning in the first place. Once we get past that we are able to rebel, not against a non-existent god, but instead against our fate to die.
Here, to rebel means to reject the idea that death must have any hold over us. Yes, we will die, but we shouldnt allow that fact to inform or constrain all of our actions or decisions. We must be willing to live in spite of death, create meaning in spite of objective meaninglessness, and find value in spite of the tragic, even comic, absurdity of what goes on around us.
Thus, existential nihilism shares with other forms of nihilism the idea that life lacks any objective meaning or purpose because of the lack of gods to provide such purpose. Where they differ, however, is in the fact that existential nihilists do not regard this situation as a reason to despair or to commit suicide. Instead, given the right attitude and understanding of life, the possibility for personal meaning is still possible.