Your answers raise more questions.
How many women has Darling been married to legally, ie, by the rest of the world's definition? How many women has Darling been 'married' to by his own definition? Does he make a habit of bringing new women, or new women with children, to family holidays every second or third year, or are you and Chatty and his current wife the only ones, ever? As far as I understand, you've been seeing him less than a year, right?
Is he expecting his family to immediately embrace you as a daughter-in-law and your children as grandchlidren? Is he (or you) expecting them to shower your children with gifts at Christmas? Have you ever met any of his family before now, and in what situations?