Buddha had already given them up by the time he sat underneath the bohdi tree. His quest in his mind was sink or swim. Of course in the beginning he probably missed his family. But his quest was one that meant the ending of suffering for all beings. In this way when he realized enlightenment he spread the path to all he met. I truly think that he would have chosen to willingly reincarnate if that would enlighten at a faster rate than the other options that are available to an enlightened being.

Buddha also taught that we have been on this wheel so long that every being has been our parents at one point so perhaps he realized a greater love for that of all beings.