It was not love he feels towards Sansa, but neither was it lust. Well, most of the time it was not lust. It is longing. Theon didn't long for Sansa herself.

Mostly, he longs for what she represents.

She is a perfect little lady. Polite, refined, and while quite lovely now, showed the potential of great beauty. She is everything a true lord would want in a wife. A wife that the Lord of the Iron Islands would deserve. If she was his, she would be a noble lady to her noble lord and then no one could deny his right to a lordship. If Theon returned home, with none other than Eddard Stark's own daughter as his bride, then they wouldn't dare to argue his rightful place as future lord to his homeland, even thought it was a land he barely knew outside of books and word of mouth.

But it was not just the Iron Islands he desires.

He wants to be a part of them, a part of the Starks. He doesn't want to become one and forgo his iron blood, but he wants to be accepted by them. He knows he could never become a Stark, but a Stark could become a greyjoy. With Sansa as his wife he could be tied to the Starks even when he finally returned home to the Iron Islands. With her, he would not be abandoning one family for another, but combining to create his own family. Not a family that he hardly remembered and couldn't picture in his head, and not a family that he could never truly be a part of. With Sansa as his wife in the Iron Islands Theon could have a family of blood and the family that he grew with.

If he were married to Sansa, then Robb could be his brother in true and Lord Stark could be his father. Then Theon would no longer be treated with less kindness than was showed the bastard.

Sansa was attractive, elegant, young, and could give Theon the family he had always wanted.

But Lord and Lady Stark held little love for him, which he knows, and would never want him as a son.

Theon knows this well,and yet it does not stop the dreams and the hope.

It does not stop that Sansa Stark is the only woman he does not crave only for body. It does not change that she is the only woman he can see himself having a future with.