A Separate Peace focuses on the friendship between two sixteen-year-old boys, and it's…complicated. Friendship is a combination of admiration, respect, jealousy, and resentment. For all the camaraderie between them, these boys are still driven by good old healthy competition, which at times can end up being, well, less than healthy. Friendship blurs identity, as one boy begins to assimilate the life of the other. You know, Talented Mr. Ripley-style and all.
Gene and Finny form a closer, stronger friendship as the narrative progresses.
Gene and Finny are closest when the narrative begins, and move gradually apart as it progresses.