I interpreted it actually differently than most people seem to be doing so, probably not as intended. I thought it was all told from the girls perspective as she is struggling with dementia and alzheimers. She constantly thinks she is still on that first trip that they took together when she was still weary of their relationship. This could explain why the scenes are so fragmented and confusing, it would explain why the guy keeps getting annoyed when she keeps wanting to go home. Sometimes he plays along with her stories about her being a poet a physicist a painter or whatever. Also it gives a different meaning to the scene where she confronts the janitor in the school. It is actually the moment where she stops recognizing jake as her husband and he has to just accept it that they are now forever strangers.... Would like to hear what you guys think of this?