Fabian is you fiance who had been madly in love with you before his accident. with his amnesia, he believes that his ex girlfriend is his current girlfriend, and now he's even more convinced since his ex showed up at the hospital since she couldn't get over him. since you arrived later, he has no desire to believe your words, and sees you as a random stranger who's weirdly obsessed with you and making up false claims about you to fool you.