Dementia. Any advice?

I guess it all depends on exactly what type of dementia one has as to how long it can last. I know someone who is in year 21 of having Alzheimer's, though they haven't been combative for years.
But with all the dementias the various stages(combative being one of them)all do eventually run their course.
Have you talked to your loved ones doctor to see if there is a medication that might help with this phase? If not, please do, as I'm sure there is one(or two or three or 4).

Until death, actually. Some dementias such as frontal-temporal disinhibit (because of destruction in the frontal lobes) and behavior is more and more combative and inappropriate.

Contact MD to discuss possible medications that can be tried.
Good luck.

It's different for each person. Your person's behaviors should be discussed with their doctor and their medications should be adjusted.

Scottis, are you still dealing with this situation that goes back to October 2021?

https://www.agingcare.com/questions/husband-keeps-accusing-me-of-having-multiple-affairs-untrue-but-he-keeps-ordering-me-out-of-the-home-470907.htm

Decades