I have a friend who,about three months following gallbladder surgery, had serious complications from diverticulosis(never knew she had the latter until she had to gb
out and started having trouble 3 months later). She nearly died, a woman in her early 50's. Maybe just opening people up fast-forwards existing problems into a crisis.
If your mother's stone was stuck in the common bile duct, it can be very dangerous to remove it. Is that the duct that was damaged? Maybe your mother was not given proper diagnostic care because of her dementia and the fact that some doctors have trouble coping with both failing bodies and failing minds. And the anasthesia may have made her memory worse. Your mother is fortunate to have a child who cares so much and stands by her through this. Thank you for the update.