You were suppressing your honest and truthful thoughts with alcohol, which is the way that a lot of people, including myself, do it. You stopped using alcohol. Now you can't stop the thoughts of the past from haunting you. It isn't PTSD. It is the pain of existence. It won't ever get better. Every moment of every day, you will think about all the mistakes you made, all the pain you caused everyone else, and the pain everyone else as caused you. Alcohol makes your brain myopic. You can focus on a brief distraction for one moment in time, and not think about anything else. And now you don't drink, and you have the delight of thinking about everything awful all at once. You won't be happy, it isn't meant for people like you and me. You have to choose. What kind of life do you want to live? You have already acknowledged your feelings, so you have three choices left, to paraphrase Tolstoy. Live life to the fullest, in the most Epicurean sensibility. Eat, Drink, Fuck, Be Merry, and Ignore that dreadful feeling that you are indeed bringing more misery into this world. Readily acknowledge how awful life is, and what you have done to further its' misery. Do nothing, and be a coward. Or be Brave, and fully admit that you are fool, and this Existence was a trick played upon you, and refuse to play the game. You'll have to kill yourself.