I still say, she is enormously jealous of and intimidated by other women, who outrank her status and who are more beautiful, clever, ....etc.
Izzy is of royal blood and will always be accepted in Royal Circles....Mosh is a pretending bogan bitch, who had the luck to be at the right place at the right time...but she also knows very well, that the higher one climbs, the deeper one can fall.
Every upcoming female princess in this family will be considered a threat and thus treated accordingly (clothing, behaviour, attention, etc.)
And that insane jealousy is going to make her the mother-in-law from Hell once Christian marries. Any woman who takes up with him in 20 years or so had better be ready to defend her life against sneak attacks.