I think we need to be very careful about tendering possible diagnoses about such mental conditions as Dementia or Alzheimers Disease. We are none of us in a position to examine let alone diagnose Prince Henrik. Even a qualified psychiatrist cannot do so. However, I think it unlikely as he has been angry about his position in the DRF since Crown Prince Frederik reached his majority at 18 and he is now 49!
I think it seems logical to assume that he is self-centred and self-absorbed or perhaps it is that he has spent his entire adult life being overindulged and now he has thrown down the gauntlet in an attempt to get his own way about the one thing he was never allowed. Whatever the cause,
his public behaviour has been so appalling that we can only imagine how badly his private behaviour has been. That there is a less than close and loving relationship between he and his eldest son is obvious and the public humiliation heaped upon Queen Margrethe, the DRF, and worse, the Danes themselves, make this a lose, lose, situation.
Whichever way you look at it there is going to be a winner and a loser and I do not think Margrethe's abdication will help because his son would still be higher than him and I do not believe that the Danes themselves are in an "abdication" state of mind. Should Margrethe be forced to abdicate because this, it will mean she has to break her vow to her country. Should she chose divorce, she will have to break her vow to her husband. Both of these vows were made in public and before God. She would not easily recover I think.
My sympathies lie with QM, her children, grandchildren and the people of Denmark. My prayers also.