My dad died on January 1, 2003. His death was very sudden and unexpected. I still struggle with tremendous grief over him. While I have never experienced exactly what you are describing, I do feel that my dad visits me from time to time in my dreams. I believe this to be him because these are not your ordinary dreams. They are real. Vivid in nature to the point where I can almost touch him. Our conversations are very detail oriented and it usually focuses on a difficult time I am experiencing or even personal achievements. Most people probably think I am crazy but my wife, my mother-in-Law and my brother all believe that this is my dad visiting me. It's wonderful.