Yes, You get what You deserve for believing in his lies, for fooling around with him when You knew he was married. He never and will never love You but he used You and that was wrong. For this, I am sorry. Why, because I also know what it feels like to be lied to and used.*
This happened to me recently. My heart was breaking inside but I sat there smiling and laughing and acting like I didn't care long enough that they believed I really was okay. Then I excused myself to the bathroom to go cry my eyes out. Fun.