As a preface: I have never seen the television show, "A Game Of Thrones," but I'm a massive fan of A Song of Ice And Fire. I've posted my Stark tattoos on GT several times, and my moniker on here provides no doubt to where my loyalty lies.
Sansa Stark's POV's have always been some of my favorites in the series. Martin appears to be setting her up as the Queen on the Chessboard. Sansa is also at the center of a prophecy of great interest to many readers.
First, let's compare Sansa to a well-known historical character: Elizabeth Of York. It's well known that Martin draws from historical events as catalysts to events in his novels. For example, the Massacre of the MacDonald Clan at Glen Coe partially inspired the Red Wedding. The chaos in Westeros is reminiscent of the tumultuous War of the Roses, in which there were numerous claimants for the English Throne. One of the figures from that conflict has some startling similarities to Sansa: Elizabeth of York.
All things considered, Elizabeth lived a relatively benign life until the death of her Father in 1483. Sound familiar? Although Elizabeth's Father wasn't beheaded, profaning the Sept, (he had died of what appeared to be natural causes) his death was the catalyst of many unfortunate events to befall the House of York. Elizabeth's two brothers were imprisoned in the Tower of London, never to be seen again. (At this moment in the story, there are parallels to the Greyjoy siege of Winterfell, with Bran and Rickon being supposedly "dead," when we readers know that they are really on the lam). The Lord Protector of the realm then became Elizabeth's Uncle, Richard III. Richard III then declared her parents marriage illegitimate, making Elizabeth a Bastard. (Unfortunately, her new name was not Alayne Stone). Several historians make the argument that Richard III was considering marrying Elizabeth of York. When Richard III fell in battle, Margaret Beaumont had other plans- to marry Elizabeth to Henry Tudor, who had declared himself King by right of conquest. They were married in January 1486, she gave birth to Henry's first child and heir, Arthur, that September, and her coronation as Queen was held in November of the following year. Also, in an interesting note, a trait that distinguishes the Tudor line from others was originally Elizabeth's- her red-gold hair. Much like Sansa's auburn locks. Because of these stark (ha!) similarities, one can argue that Sansa's "bittersweet" ending at the end of the series will be her ruling beside a handsome Knight, while suffering great losses. Elizabeth of York also provided legitimacy to Henry VII, through marriage, so this parallel could prove that Sansa will do the same. To Aegon, perhaps? Both Aegon's and Henry VII's lines were barred from succession and driven from their land. Henry came back with a small force, (from France) gained a following with the common people, defeating Richard III and claiming the throne. This is similar to Aegon landing in the Reach and possibly doing the same. Also, Henry VII's house symbol? A dragon.
Also, on page 491 of "A Storm Of Swords," Arya runs into an interesting character, this being a dwarf woman, "The Ghost of High Heart." While drinking sour wine, The Ghost of High Heart ruminates on a recent dream she had.
" I dreamt a wolf howling in the rain, but no one heard his grief. I dreamt such a clangor I thought my head might burst, drums and horns and pipes and screams, but the saddest sound was the little bells. I dreamt of a maid at a feast with purple serpents in her hair, venom dripping from their fangs. And later I dreamt that maid again, slaying a savage giant in a castle built of snow."
Even those that have only watched the show know that the dwarf woman was referencing Grey Wind being tied outside during the Red Wedding, which is the next line in the paragraph. The "little bells" are obviously a reference to Aegon Frey, or "Jingle Bell," who is special needs and harmless. As the killing of the Red Wedding begins, Catelyn grabs Jinglebell at knife point, offering to trade his life for Robbs. Walder Frey makes a remark about trading a half-wit grandson for a son, and has Robb is killed, Catelyn slits Jinglebell's throat while sobbing, killing him.
The next lines of prophecy are what truly pique my interest. Now, the maid with purple serpents in her hair clearly references Sansa Stark, and the Purple Wedding, and the poisoned hair-net she wore (unknowingly), although Littlefinger and Olenna Redwyne are (allegedly) the true master-minds of the event. But when it comes to slaying the giant in the castle of snow, things can get truly interesting.
Readers know of the scene of Sansa (as Alayne Stone) building a snow-castle of Winterfell, then accidentally ripping the head off of perpetual bedwetter, Robert Arryn's, doll. Some claim that this is aforementioned "Giant," But I think that this interpretation of myth is far too obvious. I believe that the "Giant" Sansa is going to take down is Littlefinger. Why? Although Littlefingers own sigil is the mockingbird (appropriate, as the mockingbird also swindles and hoodwinks) the traditional symbol of House Baelish is a titan. And what is a certain Baelish's only weakness? Sansa.
Petyr Baelish is the man that masterminded her Father's death, and is the sole reason that her best friend, Jeyne Poole has suffered through unspeakable horrors and abuse. (I believe that Jeyne's story is among the most tragic in the series). It's only a matter of time before this "Little Bird," truly realizes that "life is not a song," and takes the Giant down.