I Can't Understand Why He Treated Me Like Nothing

One thing that I could not understand was that once he began his affair, he started treating me like I was nothing. I almost didn't exist in his eyes, except to cater to his every whim. There were times that he didn't show me ANY courtesy when coming home late by giving me a call. He went on about his business as though I wasn't even in the picture. That makes me wonder what he was actually thinking.......actually, he wasn't thinking at all, except about that "other woman". I am sure that when he was late going to see HER, that he called her and was courtesous about it. What makes him think that just because he had her, that he didn't owe me any respect at all? Why wasn't I important anymore? I had such a hard time trying to get past all of this. Not only did it hurt my feelings, but I started feeling like I was just becoming a "nobody".