I think the scene with stannis wife "queen selyse", and Melly was a trip.
Selyse wanted to taste that "fiyah", or it seems that way...
Nah I think she was just feeling inferior.
Seeing the woman she knows her husband had an affair with and who now enjoys so much influence over him naked and looking beautiful just made her feel even more unsure of herself and insecure when it comes to her place and importance with Stannis.
This. I think she was envious in a way and feeling female feelings about her husband being with this young'ish "beautiful" woman... and she looks like she does.
That was envy.