Memento Movie

After I read the short story, Memento, I was really confused on what exactly the character, Lenoard, was experiencing. i wasn't sure what really happened to his wife or if he had anything to do with the accident. In the movie though, a lot of things became a lot clearer. I really enjoyed the movie although it had alot of events and other characters that weren't in the short story. The guy that Leonard was after, "John G." was a constant character in the whole movie, who I wasn't sure was or was not in fact Teddy, Lenoard's "friend" and cop. I kept thinking that he had something to do with the accident of Lenoard's wife, and I still do think he may have been the man who actually killed and raped Leonard's wife, but I am still not positive. There was also another character in the movie who was not at all in the short story by the name of Natalie. She was just using Lenoard in the movie, although she seemed likea very sweet genuine girl, at first. Later on, she uses Lenoard's condition to benefit herself and to harm her boyfriend who thinks she did him wrong. The part in the movie about Sammy Jankis was also another part in the movie that I really enjoyed. It gave the plot a twist because Lenoard indeed, finally found that he had encountered the same, or similar, disease that Sammy Jankis had had. The story, overall, is a little dark and disturbing in some parts, but I think it's a really interesting story and seeing the movie helped understand some of my unaswered questions I had immediately after reading it. I still wonder who "Teddy" really was and what his intentions were. He seemed very sketchy the entire time and used what he knew about Lenoard, and his condition, to maybe keep himmself out of trouble. I think he may have convinced Lenoard that they had found this "John G" that he has been looking for that he had already found him and killed him. The only unanswered question that I have about this story is about who Teddy really is in the story.