In the aftermath of her confrontation with Zelena, Regina is just furious. In an attempt to bring herself down without setting something on fire, or possibly even murdering someone, she seeks out Robin. So naturally, her first stop is his room. She doesn't stop to think that maybe his memory is something personal; the fact there's going to be a memory in there doesn't even cross her mind, honestly. She doesn't find Robin, but she does find something that shocks her out of her rage.

She watches the memory through several times, eventually sinking to the floor to and watching it a final time. For all their status as fairy tales, stories, legends, whatever, it's the little pieces that never get told that matter the most. It's weird watching it without the star player, but it gets to her all the same. She's sure she's about to get a surge of anger from Zelena for making her feel this way, but she doesn't care. The scene is halfway through when she finally stands and leaves.

Regina finds him in the diner, sliding into the seat beside him without a word.