go talk to a wall
After Squall makes SeeD — and Seifer doesn't, due to his disobeying orders during the mission — he attends the graduation ball in his new uniform. True to form, he keeps to himself, brushing off the other new SeeDs Zell and Selphie and doing a good impression of a wallflower. That is, until a young woman approaches him and drags him onto the dancefloor.
This is one of the most famous scenes from the game, and seems to hint that the romance will be off to an early start, but the fact is that Squall barely exchanges a handful of words with the girl. He tells her he can't dance to try and get her to leave him alone, although the FMV (and his later dialogue with Quistis) prove he's an excellent dancer. He just doesn't want to be there, and he does try to walk away in the middle. The girl is adamant, though, and Squall eventually relents and finishes the dance with her. If she hadn't left as soon as the song ended, he likely would have taken that opportunity to make his exit, and been no less rude about it.
I imagine that Squall didn't make a scene at the ball because of how public and important it was. No matter how much he absolutely did not want to dance, he didn't want the attention of every single SeeD and instructor in Garden on him if he pushed away some visitor in the middle of the dancefloor. For all he knew, it could have been an important client he'd have to work with later on as a SeeD. After all, Squall is pragmatic.
But, well, that doesn't mean he's not also a complete asshole.
Here's the thing. Quistis is trying to confide in him. He's probably the only person she's told about her demotion. She's reaching out to him for support, and Squall both has no idea how to give it and doesn't give a fuck even if he did know. He literally tells her a wall would be more receptive to her troubles than him. Squall Leonhart is a self-absorbed 17-year-old kid with no interest in anyone's troubles but his own, and not once does he ever show any remorse for completely brushing off Quistis.
There are reasons for his behavior, of course, just as there are reasons for why Quistis goes to him rather than someone else, but at this point in the game they're not known to the player. Instead, it further emphasizes what a jerk Squall is, and provide another point of reference on his moral compass. When the two of them leave the training center, they come across a young woman being attacked by monsters, one who recognizes the both of them, who Squall doesn't hesitate to help.
He'll protect the weak without a second thought. But emotions? Count him out.