she cared about Naruto from a point in part 1, actually she started to understand him, Naruto and Sakura have grown together and she knows him better than anyone and understands him. Typical teen girl to love the cool guy and ditch the class clown. All the other girls except one loved sasuke.I'll tell you why no one likes Sakura:
1. She loves a guy who doesn't care about her, only because he looks cool.
2. For a long time, she had no consideration for Naruto, in fact even despised him when he was clearly a better shinobi. She didn't give a fück about his feelings for her when Sasuke was doing exactly the same thing to her. When a character shuns the main hero, it's only normal that fans will end up hating that character.
3. She cries all the time, unlike other females (Tsunade, Hinata, Temari...) who have more balls than most male characters in the series.
4. In almost all the fights she gets into, she turns out to be useless and steps aside as a spectator (against Zabuza, during the Chuunin survival exam, against Gaara, when Naruto met Orochimaru/Sasuke again in Shippuden, when Sasuke killed Danzo...) In fact the only battle she ever truly fought was against Sasori, and most of the work was being done by Chiyo.
5. She's just boring, doesn't really have that much personality. Who is Sakura, exactly? We don't know about her family, don't know her views about the war and other topics... all we know is that she's desperate for a guy who didn't like her, that she has a hot temper and that she's a medical ninja. Of course there's plenty more details but that's really the essential.
You can only blame Kishimoto, because frankly he sucks at writing proper female characters. Even Tsunade and Hinata are, in the end, supportive characters. There's not a single female Uchiha besides Sasuke's mother, there's not a single female among the top 10 strongest characters... really it's the old fashioned type of story where females are there to make sandwiches and cry when they are not happy. It really surprised me that Hinata had the courage to stand against Pain, but there's no way you'll see Sakura do something like that.
Instant bias post from the time you put Hinata in there for having balls.... LOL chiyo told Sakura herself she had spirit to rival even a man. Hinata has had like 2 moments that shown a little development from the usual shy her.
Most of the work was not done by chiyo, even when she used her as a puppet she still had to attack with her CES chiyo was only there to assist her with sneaky attacks also she was using one arm so sakura has to rely on herself more.
How many other females have fought and carried it on their own, or fought and turned out not to be 'useless' ? I thought so. How many fights has Sakura had the privilege of participating in in shippuden as well.
Her one battle with sasori tops all the female fights aside from Tsunade. JS
You call Sakura boring and lacking personality? The girl who is well spoken and doesn't take crap from anyone? The one who yells out 'shanaroo!!' when she pumped and ready to go. Havign a hot temper is part of someones personality tho.
She was 'desperate' in part 1, and it changed from that child like love, she cares for sasuke more than she loves him so to speak at this point in time since he left. She watched him walk down that dark path and that was her biggest concern when he was leaving.
You are right Tsunade and Hinata are supporting characters, it is what they were designed to be, she was made a heroine and she will continue doing just that.