I am not sure if this is your speed, but check out Upper Captiva Island, FL. You have to either fly or take a boat ride there, it is very isolated and quite and absolutely beautiful. You can totally be secluded, just unplug, and have a very quiet romantic honeymoon. I don''t even know if there are hotels, you do condo/cottage rentals instead. Not even cars are allowed...you get around via a golf cart or on foot, bike. It''s really quite a special place. Very relaxing.