I think Sansa ends up with Tyrion at the end of all this
I think Tyrion has some hand in saving her from Baelish and offers to null and void their marriage since they never consummated
I, no Crackpot, think it will sort of be the opposite. Winterfell will be surrounded by the Others, but Tyrion, one of the dragons, and a portion of Dany's army will come and drive them off for the time being. Tyrion tells Littlefinger to yield his army to him to take down the Others, or else Winterfell will face the wrath of the dragon. Littlefinger refuses, and battle commences, but Tyrion chooses to not use his dragon to burn down Winterfell due to his respect for the old castle and not wanting to anger the old gods which he's felt there.
Littlefinger runs down into the crypts and Tyrion follows him. In the crypts, Littlefinger ambushes Tyrion, and almost kills him. Unfortunately for him, Littlefinger does the classic villain monologue on telling Tyrion how he outwitted him and his highborn cohorts every step of the way, how he's tried to get him killed numerous times but he's managed to slip through his fingers each time, only for each time to work to his advantage. As he's finally about to kill Tyrion, Sansa stabs him through the back and it goes through his heart with the same dagger Littlefinger used to frame Tyrion. Littlefinger looks back and realizes its Sansa, and dies below Ned Stark's statue. Sansa and Tyrion then unite their armies (while mutually agreeing to null their marriage) and march forth to join with Dany and Jon's.
This post was edited on 5/20 at 2:51 pm