A few years ago I saw a film (or at least I think I did). My memories are terribly vague but perhaps someone can help me.
The film was set in the modern era. The protagonist is a woman with a young child. She is trapped in some mental facsimile of her real life, as the result of a near-fatal accident. Ostensibly the story is standard drama about the events of her life, growing old, et cetera. Towards the end it becomes increasingly obvious that none of this is "real", and the film ends with her (now an old woman in the fantasy) accepting her fate.
The accident was almost certainly a car crash, brought about in part by the protagonist being distracted by her child in the back seat. The details of the fantasy are it was either constructed by her subconscious during her last few seconds of life, or the crash rendered her into a coma and the rest of her life was a dream. Throughout the film, clues the real world filter into the fantasy. For example sentences said immediately before the accident or at her bedside occur in the fantasy but in different contexts. Towards the end she becomes more aware of these.