I am kinda jealous personally never having experience this kinda love, but one time I ran across a guy who had his gf face tatooed on his fore arm and told him he must really love her. He was a young black man and he told me he had to do it for her cause he strayed. It was the only way to get her back he said.
My mother was in a coma and I could tell by her eyes that she was getting what I was talking about. If you know your love one you will be able to tell even the slightest eye movements or facial ticks. This fellows mother says he was conscious, I believe her! Been there myself. ps the nurses and doc, also did not get the on target facial expressions, but I know how her face moves and her opinions, so there was no doubt she was aware.