A Terrible, Wonderful, Living Dream

What happens when a new mares comes to Ponyville and becomes an integral part in everyone's lives? With a past to make many shudder but the chance to have a life outside of that and a kind disposition, who knows what'll happen? And what else is brought along? Nightmares, strange memories, shocking revelations, a death nopony would expect, a love of the same ilk, and much more.
(Sorry the description is poor right now. I will update it as the story gets further and I decide on a few things I'm unsure about right now.)