The way I understood it is, the ML and FL end up together but the ML goes on a 2 or 3 year long mission, and after that he would come back. He was not going to go first but the FL told him to go because she didn't want him to change who he is, because she fell in love with who is.
He was not going to go first but the FL told him to go because she didn't want him to change who he is, because she fell in love with who is.