One idea is that my wife was killed in the chaos and global destruction that followed the reformatting, but because of my true denial of her death and the power of "magic" such faith possesses, she has been left in a state of undeath - and I'm unsure as to whether or not she is even aware of it.
She visits me, not in a haunting way, necessarily, but certainly not in a good way, either. I live in exile, because the type of magic I possess is dangerous - thoughts and belief can manifest themselves in reality -- from a "quantum physics" standpoint, if I observe it in my mind, in the multi-verse where all is possible, I can make it so. (No, that wouldn't be so blatantly put in the story...too heavy, too inaccessible, etc).
MY character has finally decided, though, that he must leave his isolation and travel in search of those that can either help restore her...or release her.
One of the concepts of magic is "diplomacy" related in a way -- strength in numbers. Just as I can manifest magic through "mental observation" of my desires, others can as well. Whole communities have been transformed to reflect the thoughts of them...a liberal arts college becomes what would, for all intents and purposes, be an elven village of artisans and earth magic. A violent neighborhood may likewise be transformed into the lair of violent creatures. And so on...essentially, an attempt to bring classical "fantasy" beings into existence in a future-chaos setting. When there is a combat involving magic, strength in numbers is sometimes enough to counter the magic of others, as long as the collective thoughts believe strongly enough. Therefore, a village, for example, can set sentries to "shadow" the village - so simply believe, collectively, that they can not be found, and thus it can not be, unless perhaps a larger force seeks to find it.
Anyway....those are some of the initial thoughts.