With my husband's dementia, (we are in our 4th year now) I believe that a warm hug, saying "I love you", "you are the best thing that ever happened to me", a smile, a little back rub go a long way to support him. I remind him of all the wonderful things we have done together over our 45 year marriage. I take out one of the scrap books that I have put together over the years to remind him of what a great life we had together. Sometimes he remembers, sometimes not. I tell him frequently that whatever problems he faces, he is not alone. No one knows how the dementia journey will unfold. True of life in general. I reassure him that we will face whatever the future brings together, that we have been and will continue to be partners for the rest of our lives.
I know that as dementia progresses the ability to communicate effectively verbally gradually diminishes but I think that the emotional need for reassuring physical touch never diminishes and is sometimes the only way left to communicate with a person with dementia. The ability to read your body language and tone of voice lingers long after verbal communication is lost. I think it is important to validate his feelings, and ask what you could do that might help him feel better. I have received so much support on this website. I encourage you to keep posting what you are going through. There are so many caring people on this site that generously share their experience of how they have learned to cope with this awful disease. Also educate yourself about dementia, how the various types often present, how to have a positive approach to caregiving. I heartily recommend Teepa Snow's Positive Approach to Caregiving website where you can see what classes are available live online. I took the Champion series and learned so much. "Knowledge is Power" God bless you and your husband.