The thing is, if god exists, all is hopeless, because everything is arbitrary (at the whim of said god). Only without a god is there any hope for us humans to make sense of things.
I think in a way the existence of god would be very depressing, because it would make everything meaningless.
There is a caveat to this assertion; If said god is entirely internally consistent, then his whim is no more arbitrary than the laws of nature.
Perhaps this is contained in the definition "God", perhaps this is why religious types are always on about "holiness" (which I have gathered mostly means "internally consistent") .
I think in a way the existence of god would be very depressing, because it would make everything meaningless.