[@Lucas Tallador]
Jack really didn't have a reason because he was always on Earth anyways and since Thallie was one of the most determined people he knew and [i]she[/i] gave up, that's honestly his reason for leaving because if she thought it was hopeless, then why should he stay? I didn't know what reason I could give him since he was on Earth all the time. If you could help with that... that'd be great. xD

Also, Jack Frost's name is Jokul Frosti and he was, originally (in Norse Mythology) an Ice Giant, not a god. xD