Here's another thought someone speculated on another board. It could be possible that Felicia DOES now remember Peter is Spider-Man after their break-in hotel sex and is just pretending and lying to Peter that she doesn't. The art does show in the scene where Peter and Felicia are in bed together right before she leaves that while Peter is asleep, her eyes DO appear to be looking back at him, with the next panel showing Peter alone and with a pillow over his face. Although, it's very likely that was done to initially make readers think Felicia broke her promise "not to look" as another sign that Peter cannot trust her and what a mistake he's making getting back together with her. However, since it's supposed to be dark in there as well, perhaps it's supposed to be she couldn't really see his face clearly, even though she did try to take a peek and just covered it anyway.
Also, if she does indeed know now but is not telling Peter because she strictly wants a sexual relationship between them, then it shows just how manipulative she really is and how little she actually cares for him beyond a physical level even with her memories having returned. So it still undermines how she emotionally developed as as character over the years, IMO.