Baby don't hurt me ... don't hurt me ... well you know the rest (if you know the song) ... I also could have written "love is a battlefield" .. because the man is a soldier (forgive my over explaining, but some may not have seen the movie - so no pun intended). Will that even matter for you? Tough to say to be honest.
There is romance in the air, there is a shy first flirt ... and then there is a back and forth (timeline wise) to show us where the characters end up "today". I would say what the movie might be hiding under the guise of a twist ... I think is quite clear ... we are not blue (whatever that may mean) ... I do like the color, but that is besides the point.
The movie is there to show that we should live life to the fullest - to enjoy and cherish even the smallest moments. And also to do what we love to do ... with the people we love to do it with (no pun intended once more)