In my opinion (and experience) most people who marry and begin to cause friction between a spouse and their previously loving and supportive family are, well ... damaged. Sad in itself, yes. They themselves are usually from dysfunctional/broken families who are, or were, never close to their own siblings, parents, etc, and they resent the closeness - they just can't understand it and they don't want to understand it. No matter how much their partner, or their partner's family tries to make them feel accepted, loved, special, and involved ... the matier their spouse seems to be with their own family members, instead of joining in with, and enjoying and embracing the closeness, they'll do their utmost to cause trouble within the family because they themselves aren't familiar or even comfortable with such a situation.
As I said, it's sad they're damaged, but we should always beware of anyone whose intent it is to ridicule and pick faults with your family members (for no good reason obv) which usually results in causing bad feeling, a break-up, separation ... it's usually a ploy to keep you all to themselves, to control you, to get you away from all your family, friends and support system, to mould you into the person they want, without interference from anyone. People like that are worth watching and should be avoided at all costs. Unfortunately it's a bit late realising this after the marriage, after you find yourself at odds with a previously loving family, and especially after kids come along to seal the deal.
Is Meghan one of these 'controllers', playing the long game?