Each direwolves Fate represents how its owners story ends
Lady: dies as a puppy by the lannisters, to represent Sansa losing her innocense to the Lannisters
Greywind: Killed by crossbows at the Redwedding, just like Robb and both get decapitated
Nymeria: Gets betrayed by the Lannisters and flees, comes back to reject staying with the Starks
Summer: Dies inthe Three Eyed Raven's cave, just like Bran Stark "dies"
Shaggydog: killed by the Umbers and brought to the Boltons with Rickon, Who is killed by the Boltons
Ghost: Is scarred and battle worn, but returns to the Wall to serve and live up North, the same as Jon
submitted by /u/Wigglar88