The central turn in "The Theory of Everything" is not a sudden twist but a gradual, painful evolution: the dissolution of Stephen and Jane's marriage. The film meticulously builds their love story, founded on her vow to stay with him for as long as they have. The spoiler is that this profound love ultimately is not enough to survive the immense pressures of his severe disability, his global fame, and their diverging personal needs. The narrative reveals that Jane develops a deep, loving relationship with the family friend and choirmaster, Jonathan Hellyer Jones, who provides the support and companionship she desperately needs. Concurrently, Stephen grows close to his vibrant and assertive nurse, Elaine Mason.
The climax of this dissolution occurs when Stephen announces he is taking Elaine, not Jane, to an awards ceremony in America. In a quiet, heartbreaking scene, they both acknowledge their marriage is over. Jane's line, "I have loved you. I did my best," encapsulates the tragedy and truth of their situation. The film's ending subverts the traditional romantic narrative. Instead of 'happily ever after,' it finds a different kind of resolution. Stephen marries Elaine, and Jane marries Jonathan. However, the final scenes reveal a deep, enduring friendship between Stephen and Jane. His final line to her in the garden, as they watch their children, is "Look what we made." This reveals the hidden meaning of their story: their marriage wasn't a failure, but a transformative journey that created a family and enabled greatness, even if the romantic love couldn't last. The film's final shot, which rewinds their entire story back to the moment they first met, reinforces this idea—that the beginning and the journey itself hold a beauty that transcends the ending.