I dislike most sentences started in such a way. Out of the Library the other day I happened upon a conversation which had a sentence like that. It went: "I feel like morality is all in our heads, a social imposition and requirement. It really isn't real." Immediately I was thrown back to my freshman year...
I remember thinking something very similar. As a student of history I realized it very early on; morality is a relative creation of the society in which one lives. Moral codes have changed throughout the years and will continue to change as the world around them changes. Morality is, now that I have come to rationalize it, a creation akin to government and religion. In fact these three play off each other frequently. All of these, in my humble opinion, are solid. Real. Definite.
They are definite because in some way, they are based off the land. These all spawn from the need of many to share, in some way, a definite set of resources. The set is bookended with brackets on both sides. Changes in these three basic human constructions reflect changes in environment (or methods to exploit the environment). They exist because someone at some time found it necessary to construct them in order to make life easier. The organization these structures provide created the way of life we lead today.
Recognizing that a system is flawed and relative is only the first step in the thought process. It is the knee jerk reaction when one finds a contradiction in anything. It is akin to the revolutions in art. A fault is found, a gap in logic, and a reaction subscribed to change the establishment. However, as the revolution cools, it becomes logical to once again codify it. In the same way, to recognize that morality is indefinite is only the first step to realizing that it is definite. Once one asks "why was this here in the first place", the answer will lead them to cherish the nature of morality. Organization is, and will continue to be vital for some semblance of survival on any level. God help us when it is no longer needed.
(I LOVE IRONIC STATEMENTS!)