Narrative analysis: At this point in the narrative we have a major turning point in the journey of the brothers. It is easy to see how Laman and Lemuel (who probably weren't all that thrilled with the task in the first place) would have said "That's enough, let's go home." That seems to be the point of the last phrase of verse 14. From a story telling standpoint, Nephi is making sure that we understand the tensions of the journey. Even writing this any number of years after its occurrence (Nephi might have made paper notes for a journal as they went, but there is not evidence either for or against this idea) the power of the story itself remains with Nephi.
Notice also that Nephi includes himself in those who were "exceedingly sorrowful", but clearly removes himself from those who would abandon the journey and return.