Hi Ceedee,
Bless your heart! What an awful situation to be in and how distressing that your dear husband's condition and orientation are worse. It is sadly common that AD patients become agitated when out of their normal setting. My little mother had it and became really argumentative and fussy in the Dallas/FtWorth airport, just to name one example.
My only suggestion is to play along with your DH as far as is safe. You can write a note from yourself to him telling him you love him, everything is fine, and you'll be back soon. When he asks about you and why didn't you leave a note, give him that note. There is no use debating the fact that you ARE his wife. Be reassuring and try to be patient. All of us here know how heartbreaking and trying it is.
My mother mentally youthened, forgetting I was an adult, forgetting she had a daughter at all, deciding the middle aged man in the picture couldn't be my Dad because "He's too old to be Shep", and finally asking if her mother knew where she was. I just continued to call her Mom and she didn't mind.
As much as is possible in the chaos, keep him where he's comfortable and feels safe. Is there a family home further north where he'd be settled?
My DH grew up in Hattiesburg and Long Beach, loves the coast and New Orleans, so our hearts and prayers have been with you from the start.
Glad you found us! Here you can say anything and we'll understand.
Blessings - Barbara