The first time they're separated is when the full force of Rey's feelings for Poe hit her.
She's known for a while that her heart beats faster whenever they're together. Challenging one another to a race, puzzling out a problem, or even just sharing a meal in companionable silence — the what and why don't matter, just the who and the how often.
But it's always seemed like some odd happenstance, something she's put down to the way he always burrows under her skin and throws her off balance. An odd quirk of his personality, just like his humour and brashness — or something about his presence in the Force, as if his constant state of alertness is transferring over to her.
Then he's sent on a recon mission to a distant wasteland with a few of the other pilots. Finn believes a group of former stormtroopers are hiding there, and Leia wants to confirm the tip and make initial contact.
The first day passes relatively normally. Rey trains, and she maintains the engines, and she eats with her friends. She misses Poe's insights into the goings-on of the base, of course, but who wouldn't? Sometimes his comments are serious and thought-provoking, and at others, they're irreverent and bound to make her laugh, but they're always engaging. And she worries about him, but she chalks that up to the nerves she gets whenever any of her friends are in danger. Rey doesn't think much of it, just looks forward to his return.
The second day, she grows uncomfortable. During every meal break and down time, her thoughts wander to Poe, to the point it becomes distracting. She wishes she could tell him everything that's happened since he's been gone, and in return to hear not just about the big news of his mission, the details about whether he's found the stormtroopers and any intel they have, but also the small day-to-day moments that will never make it into a report. Rey forces herself to still write it off as normal worry, but deep down, her gut twists with the knowledge that it's more than that.
The third day is when she realises she's screwed. Whenever she's not actively working, his face appears in her mind. Is Poe safe? Has he stumbled into an ambush? Will the information he finds be worth the time away? Their friends have even started noticing that something's wrong. Finn keeps shooting her knowing looks that sear through her like a blaster, while Rose constantly reassures her that Poe knows what he's doing and three days really isn't that long for a mission of this size. The worst part is that she knows all those things and is worried anyway, and that's when it all clicks together.
These feelings aren't just friendship or comradeship or respect. They're the start of something greater and far more terrifying.
A/N: Prompt: 'Everything seems simple until you think about it. Why is love intensified by absence?' fromThe Time-Traveler's Wife by Audrey Niffenegger