Chris Wallace said:
Yeah-that's what I meant.
I also would say that Lenny has alter ago or his mind has control on him.
Why I think he can have alter-ago?
Well, because of that scene, in which Teddy tells Lenny truth. Then, we see Lenny changing dress and having a new car.
He also writes "His lying" on Teddy's pic, because he didn't want to know that he killed his wife. So in this scene, we see another person, not that "Lenny" that we knew.
Why I think his mind can have control on him?
Because it is like mind's games. Mind clears his memory and makes him think like he is looking fo a killer of his wife, even if it isn't so.
Memento is one of movioes, which can be dscussed several times, but still, it will stay as very mysterious movie.
You can find answers only in your mind, not in this movie. Memento just gives you some hints on real answers.