The epilogue of "Mockingjay" states that Katniss Everdeen ultimately chooses Peeta Mellark in the Hunger Games trilogy. The characters have two children together, a daughter and a son, and the family lives in District 12. Neither child is aware that the Hunger Games ever existed.
Katniss and Gale Hawthorne grow apart after the war, mainly because Katniss believes that one of the bombs Gale developed in District 13 was responsible for the death of her younger sister, Prim. She eventually comes to regard her relationship with Gale as dark and sad, twisted by Gale's anger and his drive for vengeance.