I'll respond by telling a personal story about dementia. My mother has dementia. At times she can still seem very sweet and at least seem fairly lucid. At other times she can become extremely aggressive, as well as confused.
She lives at home with caregivers 24/7 who have been with her several years now.
A couple months ago she became very aggressive with her regular caregiver, and yelled at her to get out of the house. The caregiver of course would not leave her alone.
My mother then walked out of the house. She walked about 3 or 4 blocks ( the caregiver followed her to make sure of her safety). My mother then knocked on the door of a house, they took her in, and the caregiver called me... 10 minutes away).
When I arrived my mother was totally distraught , and irrational. I couldn't get her to come with me and go home.
The only solution I could come up with was to call 911 for medical assistance.
The paramedics arrived, examined her, and told her that her only options were to be taken to the hospital or go home. Thankfully she was lucid enough to know she didn't want to go to the hospital....and finally went home, and eventually settled down.
My point is with this disease things can go from fine to mayhem pretty quickly. And sometimes there are no easy solutions. You try and create solutions as situations arise... As best you can.
Certainly the husband's actions were a contributing factor, and I do feel bad for the cruise line , getting stuck with the public relations mess that resulted.
No story will tell us how severe her actions got. Their only other option may have been to restrain her until her husband returned.... And there was no guarantee no other incident would occur if they remained on the ship.
As someone who lives with this stuff on an ongoing basis, I for one understand the cruise line's actions.
Btw - we keep her in here home because of medical advice that the familiarity of her home is good for her, and placing her in a facility would most assuredly shorten her life. So the unfamiliarity of a cruise ship, and leaving her alone on it would not be an option I would ever consider.