When she tells the story later, to Poe and Finn and Leia and especially to herself, she never hesitated.
That story is a lie.
You could be my queen, the spaces between his words say, offering her the entire galaxy. Just choose me. Rey faces him, the man who decided to kill Snoke before raising a saber to her again, and the thought of abandoning him now hits her as a blow to the hollow part of her chest. He's not ordering her to do anything, for once. He's clinging to the last fragments of light in his soul and begging on his knees.
She can't just carve him out of her and walk away. The Force hangs between them with a constant crackle, like they're pressed up against a mirror, breathing on the glass. Whether she wanted this destiny or not, it wants her— he wants her. For a girl who grew up alone, fruitlessly watching an empty sky, being desired isn't an easy prospect to abandon.
(Later, Rey will dream of the way he always looked at her, raw and hungry, taking her apart to individual atoms. She will put a hand between her legs, pressing hard, as she stares up at the ceiling of her bunk and refuses to yield. She will hate this, but her fingers come back slick.)
She remembers Ben Solo, a boy whose father sat him on his lap and let him pretend to pilot the Millennium Falcon, who didn't understand how to fight the brutality that snaked inside his mind until it metastasized, who had fear in his wide, dark eyes as his uncle stood ready to strike him down. When their palms touched, she saw all of him, all that he's meant for, and succumbing to the rage and turmoil that once lurked in Anakin Skywalker's veins is not the limit of his potential energy.
But Ben Solo doesn't exist anymore, and Kylo Ren is not a hero or a revolutionary or a lost boy she can save. He's an angry, tortured man playing with fire and not caring who his pain burns, and when he's destroyed every last scrap he can find, he will destroy her down to the last filament.
And Rey may be a desert girl, sold on Jakku for drink money by parents who died in paupers' graves, but she isn't an empty vessel for him to fill. Even when she was scavenging to eke out the most humble life, she wasn't nothing, and now that she is friend of Finn, pupil of Luke, member of the resistance, she has so much more than he could ever give her.
Rey— not Skywalker, not Kenobi, not Solo, but someone— reaches for the lightsaber.