It's a movie about a man who has Alzheimer's and a young boy helps him to get to know a woman and go on a first date to find out that it is his son and the woman is his wife. He falls in love with his wife for the first time all over again. He dies in the end in bed together. It is very similar to the movie The Notebook.

That would be "Lovely Still" http://www.imdb.com/title/tt1150947/