Nothin' goes as planned
Her lady had declared that Brienne would travel south. They couldn't risk a raven, and it was too far for Sansa to travel safely herself, even with her brother Jon and that wild man they called Giantsbane by her side. According to Littlefinger, Lady Catelyn's uncle had taken Riverrun back from the Freys and Sansa had insisted that they lean on him for assistance in the battle to come. It would be a long journey - three months all told, but Sansa was determined to reclaim Winterfell.
Brienne had grown accustomed to the North - she enjoyed the embrace of the furs on her shoulders when she walked the castle battlements - even when she was only walking to avoid the giant man from North of the Wall who had made her his would-be conquest. His interest in her was no secret, and the fellows of the Night's Watch had taken to rolling their eyes at him or laughing behind her back - something she was more than accustomed to. Poor Ed had been caught between Tormund's lustful glances and her stolid tolerance more than once. And Podrick had taken to bravely distracting the man on several occasions. Sansa remained amused by his advances but, she had said, only because she knew that Brienne could destroy him if she truly wanted to.
She would miss the cool comfort of the North, but she would not miss that. She had never been subject to such obvious affection and it made her somewhat queasy. Having been teased mercilessly in her youth, she'd never grown into taking compliments well as an adult. One could not truly call the man's efforts complimentary, but they made her no less uncomfortable.
Everything will break
She had always been brave in combat, but her inherent mistrust of people's motives had hardened her and made it difficult for her to connect personally. Pod was the nearest thing she had to a close friend having been by her side for two years now, but his praise of her was partly-compulsory as he was her squire, one that had been forced on her no less. The only other living person who had gotten close enough to her to peer beneath the armor, as it were, was Jaime Lannister. She'd not seen him these two years, not since King's Landing. Following Joffrey's murder he'd armed her with his own sword, freshly armored her, and sent her away to fulfill their promise to recover the Stark girls. Brienne had partly fulfilled that promise now in returning Sansa to the North. Arya might still be alive, but she had not been seen since Brienne's defeat of the Hound.
Thinking of Jaime also made her queasy. It made her heart hurt if she was being honest with herself.
Despite their rough beginning with him as her captive marching south after Lady Catelyn had set him free in her charge from Riverrun, he had eventually proven himself to be an honorable man - though his sense of family duty sometimes got in the way of himself. He had lost his hand as a result of defending her. He had then come back to Harrenhal for her, idiotically (abeit, she conceded to herself, bravely) diving into a bear pit with one hand and no weapons. The two of them had then traveled with the ex-maester Qyburn for three weeks on foot. Her armor gone, she'd had no protection from the elements or thieves when they rested in the night, but she'd never felt safer than sleeping back to back with him by the fire. They trusted each other equally - something she'd never experienced before, not even when the ill-fated Renly had appointed her to his Kingsguard, and she had loved him for years before that.
People say goodbye
When Jaime had sent her away from the capital, it was as if there were a string connecting them that had snapped and caused her to bleed inwardly at the thought that she would never see him again. It was an exhausting sensation that she spent much of the time trying to ignore.
As Brienne and Podrick prepared to set out with their provisions, she felt the wildling eyeing her. She unconsciously gripped her sword Oathkeeper - Jaime's sword - before nodding to Sansa and Jon and riding out. With any luck when she returned with the Blackfish Tormund would have moved on to some other interest.
In their own special way
A/N: I do not own Game of Throne or these characters; some dialogue may be taken verbatim from HBO's Game of Thrones or George R. R. Martin's A Song of Ice and Fire. Lyrics used are directly from Andrew Belle's "In My Veins" (C) 2010.