Step Families Support Group
Traditionally, a stepfamily is the family one acquires when a parent enters a new marriage, whether the parent was widowed or divorced. This community is focused on many of the relationships and issues that may arise within stepfamilies where you may find answers from some members and you may help other members with their questions.
You didn't mention why your husband was in the dating market before you two married. If he's divorced from the princess' mother, the reason he knew how to handle princess so well was that he had lots and lots of practice dealing with her mother, the always right, full of self-righteous, royal highest, the entitlement queen herself. Else, he created the little monster himself, but now he knows how to rein in the little beastie.
Again, Kudos to him and you!
Best wishes to both of you!
PS In the years to come, be wary of the princess and always follow your gut instinct about your selfish-less, caring, loving stepdaughter. If this is the first time, her mask has 'slipped off' showing you her true nature, don't discount what you just saw. Need I say more?