Would a girl who suffered from obsessive-compulsive disorder concerning purity and creed, then abandoned prayer and religion out of arrogance and denial, and showed mockery of religion through words, gestures, laughter, or looks, or expressed admiration upon hearing something that mocks religion and disbelief, be considered an apostate?

If the girl did what was mentioned due to obsessive whispers (waswas) and without her own free will, then there is no sin upon her, as she is considered to be under duress. However, if she did it by her own choice, despite being able to resist, then what she did is apostasy. In both cases, the door of repentance is open, and she must repent to Allah, increase in good deeds, and completely turn away from the obsessive whispers. Perhaps everything mentioned is merely delusions from the waswas, and it is recommended for her to consult a trustworthy female doctor.