Hi OP, I can relate to this. I'm an expat wife too, and it was this move overseas a few years ago that put my relationship with my parents into clear perspective.
DM is v reserved (stiff upper-lip, cold, relates to animals better than people, poss AS (it's in the family)) and DF is self-absorbed. They failed to grasp that moving abroad is a huge thing, had no idea that it might be difficult, still expected me to ring them regularly in order for them to give me their regular updates on their theatre visits, their friends' antics, their health, their dogs' health, and their neighbours. Still made the snidey remarks about how I was "a bit naughty about staying in touch" and as I am over 50 I don't think "a bit naughty" is relevant any more!
I have detached a bit. I grieve for the parental relationship that I could've had but never did. I try to give my DC the kind of unconditional love and support that I haven't had.
Funnily enough until I was mid-thirties I thought my family was completely normal.
I could completely imagine my DF saying the comment your DM made to your
DH and then writing the email you received from her. Very stiff, very proper, very trying TO BE SEEN to do the right thing but massively lacking in compassion.
Was talking to an old UK friend about this the other day whose relationship with her parents is similarly dysfunctional. We wondered whether it's a post-war thing - repressing all emotions and being frosty.
Goodness knows.
Anyway,
and
to all of us, and I shall watch this thread with interest.