If God exists, then either his proclamations are what makes things moral, or some things are inherently moral, and God simply acts to inform us of what these things are. In the first case, we must conclude that morality does NOT exist. God's commands must be followed or else! In the second case God is utterly redundant. If morality naturally exists, then it can be illuminated through human experience. In fact, God only hinders human growth by telling us what is and isn't moral, instead of letting us learn through experience.I understand the argument that morality cannot exist if not backed by an absolute unquestionable authority. If that's the case then there is no real morality, because there has never been shown to be an unquestionable authority to enforce it. However, I believe that morality can exist even in the absence of this authority because, as you mention, reality exists. Our morality will most certainly be imperfect, however we can continue, as we have, to reduce the degree of imperfection as we gain a greater understanding of what reality is.
If God's morality were perfect and unquestionable then please explain to me the evolution in human morality within the "Christian world" over the last couple thousand years. I presented this argument to you before. The fact is that humans have always controlled the shaping of our morality. We readily abandon yesterday's unquestionable moral standards for those that better match our progressive notions of fairness and that better suit our current cultural "reality." Men do this, not God. Yet we continue to imagine that God endorses these updated notions of morality because God is fair and loving towards us.
We do not need to imagine that some sort of boogeyman is going to enforce our moral standards. Nor do we need to pretend that some supernatural being devised our moral standards for them not to fall apart. Our moral standards are not a matter of the whims of man, they never have been. If anything allows whim to control morality it is authoritarian religious institutions appealing to the authority of their God and who's intentions they are the sole interpreter of. Our moral standards come from a power greater than God, they come from reality.
The concept of morality only makes sense if it is a human construct created for human purposes. I can go on about this forever, but it is a pain typing on the phone.