People not liking her because of The Answer are really people just not understanding how well written a character she is or understanding her character at all. Its a cop out because "Oh man shes so bitchy" is all they can say. When really diving into her character there is incredible depth to what she goes through and honestly The Answer really hits home on that too.
Not my words but I remember reading this and it really hits home:
[spoiler](/s "Yukari is damaged goods. She was a daddy's girl but he died when she was young. Her mom has been whoring around ever since then and everybody's expected Yukari to end up just like her, pushing Yukari to build emotional barriers between herself and others. Then P3MC waltzes into her life, understanding her situation completely, being strong, tough, sensitive, and reliable, and has been saving her from danger on multiple occasions. So as the token piece of ass in the story, Yukari's expected to strip naked and throw herself at big strong P3MC like the good little damaged girl she is, right?
Wrong. Yukari's not stupid. She knows her situation is ****ed up, she knows what people think of her, and she knows what they expect from her -- an emotional skank just like her mom. Yukari is self-aware of the tropes and archtypes she falls into and she fights tooth and nail to break free from them. That's why she's so distrusting of you, she doesn't want to be the idiot hormone-addled teen that falls in love at the drop of a hat. That's why she's bitter towards P3MC's acts of heroism, she doesn't want to be the damsel-in-distress that exchanges sex for protection from a big strong man. No matter what she does her mother's reputation and her father's death will follow her wherever she goes. Her development, both in-story and S.Link is about her fighting back against the roles she feels trapped in and in the end she realizes just because she found someone she loved, doesn't mean she's proving any stupid assumptions right.
So after all this... losing him? She wanted to be strong. She didn't want to be like her mom - she didn't even want to UNDERSTAND her mom. She wanted to be independant and self sifficient...
But she opens up. She learns to trust and rely on the protagonist. She welcomes him into her life, despite how this goes against what she's been fighting to establish in her own life. In her S-Link, she says Falling in love is like giving a part of yourself away. And this is key.
She, metaphorically, gave a part of herself away when she opened up to him. And then he died, taking that piece of her with him. Leaving her feeling incomplete. Leaving her unable to completely ignore how her mother feels, among other things.
And to make matters worse? Someone inherited his special power, and it wasn't her. They find themselves in a strange rift where time is distorted and they go to the past. She can't go save him, and she's jealous that she's not the one who got his power - which would at least let her feel like he's still with her, like with Junpei having Chidori's regeneration.
I mean really. Any less would kind of be unexpected of Yukari, you know?")