My husband's children are fighting me on his dementia diagnosis.

My husband and I have been married for almost 45 years, in that time I think we have come to know each other pretty well. His children from his first marriage spend very little time if any with him as a matter of fact we recently moved back to our hometown where his one son lives. During the 5 months we have been here, this son has spent less than 6 hours with his father. My husband was recently hospitalized for another condition and now all of his children are soooooooo devoted and caring and they want to tell me how he should be treated, etc. Tonight when they visited in the hospital, I left early as I have been on long hospital vigils and needed to do some things at home. when they left, my husband called me and wanted to know why he had dementia as a diagnosis on his medical records because his sons told him it was there and there was obviously nothing wrong with his mind in their opinion. Yes, he was having a good night talking old hunting stories which he has no problem remembering but if I ask him tomorrow if his sons were there he will tell me no, no one was in. He has been given the diagnosis from 4 different doctors and they have discussed it with him but he does not remember nor does he accept. I am at my wit's end with these children and am about to become the proverbial wicked stepmother. I just needed to rant to people who might understand. Thanks!!