Here are some points to consider:
* Trauma and PTSD: Both Peeta and Katniss have suffered immensely during the war. Peeta was brainwashed and tortured, while Katniss witnessed horrific violence and loss. These experiences leave deep scars on them, making a truly happy ever after more difficult.
* Their Relationship: Their relationship is complicated. They formed a bond in the Games, but their feelings were deeply intertwined with survival and circumstance. The war further tested their relationship, and while they do end up together, it's unclear how healthy and fulfilling their relationship truly is.
* The Future of Panem: The war has ended, but Panem is in ruins. The future is uncertain, and rebuilding will be a long and difficult process. This context might make a "happily ever after" seem unattainable.
Possible Interpretations:
* They find a semblance of peace: They might build a life together, raising their children and helping rebuild Panem. They might find moments of joy and happiness, but they'll always carry the weight of their past.
* Their relationship struggles: The trauma they've endured could lead to ongoing challenges in their relationship. They might experience difficulty communicating, trusting each other, or even being truly happy together.
* They find happiness elsewhere: While they may stay together, their true happiness might come from sources outside their relationship. They could find fulfillment in their work, their children, or their connection with the people of Panem.
Ultimately, the ending of Mockingjay allows readers to form their own opinions about Peeta and Katniss's future. It's a realistic depiction of the complex emotions and challenges that come after war and trauma, making it difficult to definitively say whether they live happily ever after.