Peeta and Katniss needed to be protected from the Careers, so he couldn't send both of them or keep them both at the tree. So he split them up so that Finnick and Johanna could each protect one of them. Peeta was weakened from his encounter with the force field, so sending Katniss and a protector made the most sense.
Why is Katniss confused to see Johanna with Wiress and Beetee?
Katniss is once again confused by the actions of another tribute when Johanna tells her that she got them out of the jungle for Katniss. She definitely does not trust Johanna, and though she likes Beetee and Wiress, she is weary of teaming up with Johanna.
Johanna asks what happened to Mags, and when Katniss tells her she says Mags was Finnick's mentor and half his family. She also explains that she saved Wiress and Beetee because Haymitch told her that if she and Katniss were going to be allies she had to save them for Katniss.
Ever since their first meeting in the elevator, Johanna Mason has had her eye on Peeta. Even though she came off as cold and distant, she was never afraid to show her admiration for Peeta. In that same scene in The Hunger Games: Catching Fire, Johanna asked Peeta how he felt now that everyone wanted to sleep with him.
Johanna attacked Katniss to take the tracker out of her arm, so that once Katniss was in a District Thirteen plane, the Capitol could not track her. Johanna had to attack her because it also had to be seen that Johanna was breaking the alliance between the tributes.
Katniss Looks for Allies | The Hunger Games: Catching Fire
Did Johanna like Finnick?
Finnick Odair
Johanna and Finnick were friends prior to the 75th Hunger Games, most likely having formed a bond during previous Hunger Games where they were mentors. They were allies during the 75th Hunger Games, along with Wiress, Beetee, Katniss, and Peeta.
Johanna Mason won her Hunger Games through a simple strategy that relied heavily on her own acting ability. From the moment of her Reaping to her arrival in the Capitol, she pretended to be meek and forgettable, one of the many Tributes who end up as chaff for the thresher of the Games.
Their relationship was all friends. They trusted each other, but that doesn't mean they had romantic feelings for each other. Plus, Cinna's too old for Katniss.
Katniss's focus on survival and her family's safety prevented her from fully considering romance, but her feelings for Peeta and Gale diverged in the end. Katniss ultimately chose Peeta because he understood her trauma and she didn't want to lose him, proving her love for him.
Johanna Mason developed an addiction to morphling while hospitalized in District 13 for the torture she endured in the Capitol. When she was weaned off, she instead dipped into Katniss's supply.
The female Morphling, however, appears almost coincidentally, and Peeta even mentions that they don't know her real name. 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.
Later, the two learn President Snow considered their actions to be an act of rebellion against the Capitol. After their last interview, in which the two continue to affect their romantic feelings for one another, Peeta comes to the realization Katniss has staged her love for him all along.
Yes, Katniss did develop an addiction to the morphling, on account of constantly being sedated with it, however, I wouldn't say that she was an addict. An addict is someone who goes to a substance (or whatever their 'poison' may be) under their own mind.
Johanna remains in the Capitol for quite a while, and she and Peeta are tortured for information concerning District 13 and the mockingjay rebellion. While in the Capitol, Johanna's entire head is shaved, making her bald.
Katniss understands and asks if Peeta's been told about this, but Haymitch says he doesn't need to tell Peeta because "He's already there." As Katniss readies herself to take the stage, she realizes that, although she has made it out of the arena, the most dangerous part of the Hunger Games has begun.
Katniss didn't really have the time to consider romance when she was worried about survival. When Peeta and Gale both made their feelings clear, Katniss wasn't entirely receptive despite caring for them both. In the end, her feelings for Peeta and Gale diverged, with Peeta ultimately winning her heart.
In Chapter 9, as Caesar Flickerman interviews Peeta before the Games, Peeta reveals to Caesar and all of Panem that he's in love with Katniss. Peeta's revelation sets in motion the storyline of him and Katniss as ill-fated lovers that carries on throughout the Games.
Before the Capitol battle, Gale had explained to Katniss his series of bombs designed to feed off human compassion: a small bomb would go off, and then when medical aid rushed in, a second bomb would go off, killing those people as well. Incidentally, it's this exact type of bomb that took Prim's life.
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.
After winning the games, Snow forced Finnick into prostitution and sold his body to Capitol residents to gain their trust. Finnick only agreed to take part because Snow threatened to torture his loved ones. Even though he bedded several women throughout his time as a victor, Finnick's love for Annie remained true.
While fighting some of the other tributes with a knife he acquired from the Cornucopia, Maysilee saved Haymitch's life by killing the lone surviving attacker. As the number of tributes dwindled, Maysilee went off on her own.
Finnick Odair is the youngest winner in history, winning at just 14 years old. District 2 has the most overall winners, producing "Career Tributes" and having the highest number of victors among all districts. Warning: Spoilers ahead for The Ballad of Songbirds and Snakes!
In the case of Johanna, they each hated each other because that was what the Capitol had taught them to do. They were from competing Districts, and the idea of the Games was to keep the lesser citizens of Panem distrustful of one another and unwilling to form alliances (or raise arms in war).
