For a moment, all Peter could do was stare at her and even with the mask on, he was pretty sure the surprise was easy to pick up on. Gwen faked her death. Back in her home, everyone thought she was gone, that they'd lost her. Just like he'd lost his Gwen, just like dozens and dozens of others had lost their own. There was no body to prove to them that it was true, maybe that would keep some of them going, holding onto the hope that somehow, by some miracle, she'd gotten away and survived. Just like he'd clung to it holding Gwen in his arms, pleading with her to open her eyes and that she was okay. That it wasn't true, that she was still breathing and that--
If she went back, if people saw her, they would know it was true. If she stayed away from home, where people were missing her, they would want her to stay. Ask questions of what and how and why, beg her to stay.
A dozen of his own questions swam across Peter's mind and he looked away to try and drown all of them. To not start going down those roads of trying to understand himself. He was quiet and watched the cars below, wanting to say something, but wasn't sure what. That she could still go back? How so many people must be missing her and devistated that she was gone, just like she'd seen echoed around the multiverse out to corners Peter himself probably hadn't even dreamed of. That she should go back? Give up what she'd been doing and go home where people could still be holding on to that hope? None of the other times had changed Gwen's mind or her perspective before, he couldn't imagine one evening on a rooftop would do much more for it. Not much, not really.
She'd shown some of the cards close to her chest...
"She knew, you know..." his eyes watched break lights below light up and fade out, in some mind numbing rythem that Peter couldn't keep track of, "You mentioned being told the secrets that could have gotten you killed, but Gwen knew here. I told her, tried to stay away to keep her safe. She didn't want me to, I didn't want to, but I tried." that was what had hurt her. Not keeping Spider-Man from her, trying to keep him away from her, "....I told her I wasn't going to try and stay away anymore, and that was the night. She even showed up where the fighting was, said it was her choice and that she could help and..." and he did what he said, he didn't try to push her away. Didn't try to make sure she couldn't follow him to the power plant that night and for a few seconds when the dust had settled was even grateful that Gwen had been there at all.
Peter wished he'd tried harder...