"Stop trying to make me feel better, it makes me feel guiltier! What's wrong with me?!?"
- The whole movie has a consistently melancholic undertone throughout. While by no means as bleak as something like Synecdoche, New York, it doesn't sugarcoat the fact that life can get unpredictably tragic and our agency isn't enough to have complete control of our fate.
- The depiction of 2092 New York being a cheery Everything Is an iPod in the Future utopia with people that have gained everlasting lifespans is undercut by Old Nemo's predicament of being the last mortal on Earth: lonely, disillusioned, confused, spied on and gawked by the mass media following his final days with the anticipation of a reality show audience, and struggling to remember his past. And when he does manage to squeeze out some episodes of his life, they're all contradictory and they all present pretty sad outcomes that are bittersweet at best.
- Nemo's omniscience not really helping him choose the right path. Even the timelines with happy outcomes in which Nemo is reunited with Anna or Teenager Nemo wakes up from the coma in front of his reconciled parents, just because things turned out well then, nothing indicates that bad things will stop happening afterwards, and the bizarre Gainax Ending with time reversing making everything turn out well could be just Old Nemo's wishful Dying Dream.
- The Butterfly Effect of the waffles factory worker leaving a piece of eggshell that distracts Nemo's father leading to an accident that leads to the divorce and Nemo causing a man in Brazil to lose his job because he picked a cheaper pair of jeans offers the Fridge Horror tear jerker that our actions, even the smallest ones, can snowball into ruining someone's life.
- Nemo actually dreams of the accident his father would cause that ends up taking the life of a mother crossing the road while walking out with her baby, and tries to run outside to warn him. The accident takes a huge toll on Nemo's dad.
- Pretty much any timeline with Elise:
- They marry, but while driving away from the wedding they're involved in a freak road accident that kills Elise. Nemo decides to make himself immortal and by 2092 he travels to Mars to spread her ashes there as he promised when they bonded as teenagers, only to then die when the Sleeper Starship is hit by asteroids.
- Alternatively, they marry, they don't get involved in any road accident, but Nemo endures an Awful Wedded Life with her due to her depression and BPD. The part where Elise temporarily keeps her mental issues in check and enjoys herself at her daughter's birthday party and then sleeps with her whole family together in the same bed is then brutally undercut by her having a depressive episode the very next day in which she goes outside to weep under the rain, so much so that some concerned neighbors come out of their homes.
- Nemo does his best to be a good husband and keep their family together, but even he has his limits and eventually expresses his honest thoughts through a Heroic BSoD:Nemo: I don't know what to do... I often have this dream. Some prehistoric time, I can hear you screaming. I chase the bear and you're not afraid anymore, but when I wake up there's no bear... but you're still afraid. I'm not a bear hunter. I'm an executive at a plant that manufactures photocopying machines that just quit his job. I don't dare to move, I don't live, whatever I do is a disaster. I would so love to be able to chase the bear away and for you to not be afraid anymore.
- When Elise admits that she's missing Stefano, she breaks down again when Nemo reassures her that he won't abandon her.Elise: I hurt everybody! I hurt you, the children... this can't go on!
Nemo: Together we can do it.
Elise: If I stay here you're all gonna end up drowning with me...
Nemo: We'll learn to swim. I love you. - She decides to leave, and actually comes across Stefano while working at a beauty salon... but it's All for Nothing as he's all grown up and she doesn't recognize him, and thus she's left waiting and longing for him, holding onto a photo of him as a teenager as she continues to be unable to let go of the past.
- The Jean timeline. Paralleling Old Nemo's dissatisfaction with the future society of quasi-immortals, Nemo is utterly Lonely at the Top and so desperate to feel the sense of random chance again after casting his life "in cement with airbags and seatbelts", that he goes to the extreme of determining his fate with coin flips, which ends up getting him killed and leaving a heartbroken wife behind.
- Nemo's father really gets the short end of the stick after the divorce. At least Nemo's mother moves onto new men, Nemo's dad doesn't, and goes on to become handicapped and needing his teenage son to act like his nurse. Rhys Ifans gives an especially heartbreaking performance at the outcomes of the Train-Station Goodbye, both him crying his son's name as he runs after his mom's train, and him breaking down into tears hugging his child tightly in the timeline in which he stays, really selling his character's desperate need of love and company.
- On a minor level, the journalist interviewing Old Nemo and trying to make sense of all the contradictory life stories, some not even making sense because Nemo dies in those. Unlike the other invasive mass media figures making a spectacle out of him, the journalist approaches Nemo respectfully and records their interview with an old-fashioned tape recorder. There's a mix of frustration and empathy for the lost centenary man in the journalist's reactions and demands of knowing which recount is the right one. And to top it all off, in the end Old Nemo tells to his face that he doesn't exist, and they're both just fragments of a child's imagination. For the poor journalist's sake, let's hope Old Nemo is making it all up in a Dying Dream.
