Though only one tribute can win, a change in the rules allowed Peeta and Katniss to both win. Their victory was partly secured because of Peeta's declaration of love for Katniss before the Games.
In Catching Fire, Enobaria, Beetee, Finnick, Peeta, Katniss, and Johanna survive the 75th Hunger Games. Enobaria, Peeta, and Johanna are captured by the Capitol after Katniss destroys the arena's forcefield. Katniss, Finnick, and Beetee are rescued by District Thirteen.
Six tributes in total survive the 75h Annual Hunger Games: Enobaria, Beetee, Finnick, Peeta, Katniss, and Johanna. Katniss, Finnick, and an injured Beetee are rescued by the rebel forces. On the other hand, Enobaria, Johanna, and Peeta are captured by the Capitol and imprisoned.
Katniss does not die in Catching Fire, though she has a few close calls during the Quarter Quell. Finnick, Johanna, Mags, Beetee, and Wiress were all secretly recruited, not only to help Katniss win, but to keep her alive at all costs.
Katniss ultimately chose Peeta because he understood her trauma and she didn't want to lose him, proving her love for him. The debate between Peeta and Gale continues among fans.
Katniss made the choice to build her future with Peeta. If she didn't love him, she wouldn't have made that choice. Katniss made her whole world about getting the people she cared about to the next day, her choice to survive with Peeta proves her love for him.
Given that she is willing to make the ultimate sacrifice to protect Peeta, it's safe to assume that the Morphling was committed to the rebel cause. Like the other victors, she knows the power that Katniss has as a lightning rod for the rebellion, and she knows that Katniss will not help without Peeta.
Her third kill occurs at the end of the Games. First, she shoots Cato in the hand so he will release Peeta. Cato falls off the Cornucopia and is attacked by the mutts. Once Katniss realizes that the dogs intend to draw out Cato's death, she uses her final arrow to kill Cato in an act of mercy.
Toward the end of the novel, Katniss realizes that Haymitch has been keeping information from her and using her to help the rebellion, causing her to feel extremely betrayed. On the other hand, his goals are generally good ones.
As Katniss gets to know Finnick during the Quarter Quell, she sees he is in fact loyal, dutiful, and caring. For example, despite Mags being a burden on his chances of survival, Finnick does everything he can to keep the eighty-year-old alive because, as we learn, she was his mentor and he genuinely cares about her.
The plan is to break the victors out of the game and start the rebellion. They need Katniss because of her power and influence, but they know she won't join if Peeta dies, so they work to protect them both during the Quarter Quell.
Unable to find Peeta and hearing a cannon, Katniss nearly attacks Finnick, suspecting his betrayal, but he reminds her to "remember who the real enemy is." Katniss attaches the wire to an arrow, firing it into the arena's roof just as lightning strikes.
Chaff, of course, comes right out and kisses Katniss, though his reason is more to have fun with Katniss's image than to turn it to his advantage. Finnick's and Johanna's tactics, however, are clearly deliberate attempts to manipulate Katniss, and Katniss immediately distrusts both as a result.
If they don't interfere with his drinking, Haymitch says he'll help them. His first piece of advice is that whatever the stylists do to them, they shouldn't resist. The train finally arrives at the Capitol.
By killing Coin, Katniss ensured a chance for a peaceful and fair country, avenged her sister's death, and liberated Panem from the fascist government. The Hunger Games franchise is still an iconic series of books and movies, with the latter truly cementing the property as an international phenomenon.
She then attempts to kill herself with the suicide pill attached to her uniform, but Peeta stops her. She is arrested and placed in solitary confinement, where she attempts to commit suicide by starving herself and overdosing.
Snow can't stand to see a young woman betray a young man's affection—his view of what happened 65 years ago. And so he takes out his old, festering wound on Katniss.
Chia Mags kisses Finnick on the mouth to briefly let him know that this is the last time she will see him. It's her way of saying "Goodbye" but in a more affectionate way.
His feelings and memories are distorted with hallucinogenic tracker jacker venom, in a mind-control technique known as "Hijacking." The Capitol uses this method to turn Peeta against Katniss, making him believe that she is not only responsible for the death of his family, friends and the destruction of District 12, but ...
Peeta: "Nobody needs me." Katniss: "I do." Peeta grabs her face and gives her by far the most passionate kiss of the franchise, until Johanna interrupts.
Gale was responsible for creating weapons that would trigger a second wave of bombs to target first responders and combat healers. This invention potentially ended up killing Prim, but even if he wasn't directly responsible, Katniss found this tactic so abhorrent that she lost her affection for him.
It's only implied that they get it on via snuggling and other affectionate acts in close quarters — but if you have read the book, they really imply that they took their relationship to the next level.
