We don't know if the one who married Seth was the real Neftys or the fake one, because we are not 100% when it was that the real one got trapped in the mirror, so yeah... If she'd already been replaced by the fake one when they got married, then that'd mean that Anubis' mother is probably also the fake one too, but we'll have to wait and see to know all of that for sure.
i thought she would have been real up to the point of conceiving anubis since he felt so betrayed?
unless his brother is the one who created a fake wife prior to their wedding, knocked her up, and did all this to fuck with seth ):
the locked up nephthys always sides with seth even though shes locked up, and she always seems guilty.. maybe even though shes a fake she fell for seth and thats why she felt so bad about lying to him about anubis
IDK LOL im just glad my confusion is not mine alone..

i thought his wife was like trapped in the mirror and that the one locked up is fake
now im confused