Why did God make me?
The simple answer is that he made you because he is good. Everyone and everything that we call good is called good because it bestows what it possesses on others. "Goodness pours itself out," the philosophers say. So the good God wants you to have a share in his goodness. When this goodness is complete, we call it "happiness."
The first thing God says of each of the things he created is that it is good, and in the case of human beings, Sacred Scripture tell us that he saw not only that we are good but that we are very good. Between the goodness of our being created and our ultimate happiness lies the course of our earthly life, in which we are to know and love and serve God in gratitude so as to be happy with him forever in heaven.
Only our own sin can get in the way of this. Yet even our sin can serve to bring us closer to God—if we go to him in the sacrament of confession expecting his gift of pardon and the renewal of his mercies.