Ever since the Red Wedding, book readers have speculated about the fantastical character Lady Stoneheart, a resurrected, bloodthirsty version of Catelyn Stark from Martin's novels. Beric Dondarrion -- whom we have seen die and return to life on the show -- sacrifices himself to yank Catelyn back from the other side, and Lady Stoneheart, as she comes to be called, leads the Brotherhood Without Banners in his place. Only hers are more malicious, and focused on people who've done her wrong (the Freys, the Lannisters, etc.).
The character's worth bringing up because it appears that Sansa may essentially be taking Lady Stoneheart's place in the show's streamlined narrative. With the fiery makeover and a warrior's vitality that erupted out of her battle wounds, Sansa doesn't arrive at Castle Black just content to cozy up in the corner; she rallies Jon, rallies the troops, and plans a march back on Winterfell. When Littlefinger sneaks back on to her radar, offering Sansa the Vale's troops, she both takes advantage of and eviscerates her casual oppressor. What happened with Ramsay haunts Sansa, and in her big scene, she sharpens the pain into a spear to plunge into Littlefinger's heart.
"What do you think he did to me?"
Littlefinger replies that he "underestimated" Ramsay.
"The other things he did, ladies aren't supposed to talk about those things," she says. "But I imagine brothel keepers talk about them all the time."
Diss, Sansa. Diss.
“I can still feel what he did in my body, standing here right now.”
There's a theory floating around, derived entirely from this line, speculating that Ramsay impregnated Sansa. People, ever heard of figurative language? Nuanced emotions? Leading Sansa down this path would open a Pandora's box of victimhood that Game of Thrones isn't ready to reckon with. More likely, Sansa's internalized her pain, and is completely motivated by sticking it to the men who've given her this emotional ulcer. Ramsay is clearly in her crosshairs. So is Littlefinger.
But Sansa's grappling with revenge and reclamation. Slaying the men who've crossed her isn't enough. She knows she was "awful" as a kid -- her words! -- and she wants to put the Stark legacy back together. To her, that won't happen until Rickon is saved, the Boltons are wiped off the face of the planet, and the Direwolf flag flies atop the Winterfell keep. Sansa isn't eying the Iron Throne. She doesn't share Arya's kill list. Her first home is an end destination. But what happens after she successfully leads her Northern allies into battle? The end.