Undertale spoilers
@kara_dreamer@witches.town It's only once you attempt to Save him as well that he truly breaks down and relents, but at that point he wants to end. You return him to being Asriel but now he has a soul, he knows what he's doing is wrong and it crushes him. Hence why he can't bear to say goodbye to his parents and doesn't want anybody to know he was Flowey. :( Even he can't abide by what he did without his Soul.