"You really sold it."
Oliver doesn't answer, not because he doesn't know what to say, but because there's too much he wants to say. She's always seen straight through him and now is when Felicity decides to take him at face value? He doesn't know if she doesn't believe him or just doesn't want but just the knowledge of her doubt hurts Oliver enough to take his breath away.
Felicity said she understood, but she hadn't, not by a long shot. He didn't say it for the camera, for Slade's benefit. He'd told her so she'd know, in case the unthinkable got worse and he never got another chance to say it.
She's looking at him, uncertain and a little hopeful and Oliver can't tell what she wants him to say, he just knows he can't say it like this. It can't be tainted by the shadow of Slade and when he does tell her again, it's going to be right. Next time Oliver is going to make damn certain that Felicity has no reason to doubt him.
So he tries to smile, hopes she can't see his heart breaking and wonders if she'll ever realize that he tells her everyday without saying a word.
"We both did."