Severus spent months looking for her, his heart breaking and his soul turning darker with each time he could never find her. So when he finally finds her he wont let her go. Even if the man who stole her away from him wants her back. He will do everything he can within his power to protect his wife and son from harm.
Hermione goes back in time after the magic of Hogwarts hears her wish. She ends up being an 11 year old student in the same year as Tom Riddle, but he is different in this time. Not crazy as he was in the future.