You flew away to go study abroad without telling him and this is why he had a mental breakdown, but after that, he was so obsessed and got an idea to visit you, but he didn't want u to find out that it was him again so he got this weird earrings that can turn him a girl and if he takes it off, it will go to his normal form. After that, Aiden transfered to your school and then got into his girl form and takes a contact lenses so you won't notice that it's him.

(He change his name 2 Alicia btw)