Hi there,
I can't blame you for being annoyed, and you are right in being so.
I have had similar stuff with my relatives (adult age nephews and neice) hardly hear "thanks", so it was hard to do but I cut them off, I mean I have only one kid, they don't even send him a card, they don't acknowledge any of our birthdays, etc. it hurts a bit too, so I finally told my husband, that's it, we are not going to keep doing this anymore. Hey, I am not holding grudges, but a little respect in return would be nice.
I apologize to the viewers here if this seems childish of me, but after 27 yrs. it gets old.
So, I must say I agree with the poster her, she has a right to be annoyed, and I'd suggest doing what I have done. . . cut off the gifting, cards, etc. to those who can not take the time for your family.
You take care now,
DE