Well, he never died! In the first book, he’s Katniss’ closest friend, but doesn’t get selected for the games itself. He later reveals his feelings for Katniss, competing against Peeta, who also loves Katniss. Katniss and Gale do have a short termed romance in the second book, but eventually, in the third book, Katniss and Peeta end up together, eventually getting married and having children. Gale and Katniss’ relationship weakens in the third book, after weapons Gale designed are the cause for Katniss’ sister, Primrose’s, death. Hope this helps!
Forking rivers or paths are commonly used to express a character's opposing features in literature. In this case, it represents Nikolai's two sides - stern and caring. The river merges into one at the end - implying that his two sides can coexist.
