Is it permissible to feel uncomfortable with someone due to their appearance, way of speaking, and different way of thinking, and to avoid their friendship without hurting their feelings, or is this considered arrogance?

If the feeling of discomfort is due to the girl's negligence in adhering to the prescribed dress code and her foul language, then it is the lowest degree of enjoining good and forbidding evil, which is done by the heart. However, if the discomfort is due to worldly reasons, such as her being less social, and this leads to mistreating her, then it is arrogance and belittling of Muslims, and it is legally forbidden. As for mere fleeting thoughts and self-talk that do not settle or lead to action, there is no accountability for them. However, one should strive to ward them off so they do not settle in the heart. It is preferable to embrace the girl and try to influence her positively with advice and wisdom, praise her good qualities, and try to separate her from bad company.