She cut her way through the battle without stopping, betrayal, heartbreak, and rage spurring her on. She took no notice of the various scrapes and bruises she accumulated, had no care for her life at all. She was praying to met her end on the battle field this day, but not before she took as many orcs, goblins, and wargs with her as she could. Her heart howled as she fought. They had thrown her out, abandoned her, after all she had done to find them a home, after all she had done to save them. They had taken her heart and crushed it under there booted heels, taken everything that she was, everything that she had given them, and acted as if it were nothing more than a cheap piece of tin.
As she had stared at all of them on the battlements, she had searched for one sign, one tiny, small sign, that any of them cared at all, even if it was currently buried under gold sickness. But all that had met her gaze was cruel indifference and hot anger. And so she had left, everything that made her her ashes at their feet. She didn't know what she would do if there hadn't been the battle, but there was and so she threw herself into the fray, praying that she would wake up in Yavanna's gardens and that all the pain would be over.
But even though they'd abandoned her, a Baggins never abandoned their family, so she fought by their sides, often wearing her ring, but sometimes not. She had followed Thorin and them to Ravenhill. And when Azog had threatened Fili, her laughing golden prince that reminded her of nothing so much as her Took cousins, she slew the defiler herself, with the tiny letter opener that they had all mocked. She had jumped and thrust it into his eye, driving it in deep and killing him instantly. She had seen Fili's shock and surprise, but she had whirled away before he could speak, donning the ring as she ran.
She ran right to where Kili and his elf had run into trouble with Bolg. Viciously hamstringing him, she slit his throat before he could hurt the laughing prince, the one who had brought the most cheer to the company besides the miner that had been so dear to her heart. She had ignored Kili's surprised shout as well and kept moving. The two greatest enemies were dead, the armies should hopefully start scattering, but there were always more enemies to slay.
But by the time the battle ended, Bella found herself still standing, still alive. She wanted to rage, to weep bitterly, but knew that Yavanna would not be pleased if Bella rejected her mercy. However, she had learned something during the fight, something that the ring had not wanted her to know but it had overplayed it's hand and revealed to her that it was the one ring.
However, the ring didn't realize that she was sick of gold and power and all the madness that came with it. Firmly entrenched in her desire to destroy the wicked thing, she made her way off the battlefield and headed towards Mordor. She could destroy the ring and then figure out what to do with the rest of her life or not. The mountain had been reclaimed, her contract fulfilled, there was no reason for her to remain anymore. No reason to return to the Shire either. Maybe after she had destroyed the ring, she would take the opportunity to see more of the world. If the destruction of the ring didn't kill her first, of course.