You are taking baby steps towards healing, and working through painful stuff. It's going to hurt for a little while, but you will be stronger for it.
I was going through some things awhile back when filling out a really intense detailed job application, which included a background check where you had to answer a million questions on things you had done/not done since you were 16 kinda thing... which had to be truthful since it was part of a polygraph. There wasn't anything huge I had done wrong, but little things kept popping into my mind all day... attacking my self worth. Stupid mistakes I had made, stupid things I had done in response to the insanity of living with an active addict.
The day before, I'd been on facebook and had saw a message that said something like, "You are a child of God, and that makes you worthy and good. Your past or things you have done cannot take this away from you." That message also played in my head that day and I finally realized when I woke up the next morning that I am a "good" person.
We can't change the past, but we can learn from it and make better choices in our future. And you are on your way to a bright future. Keep pressing on! You can do it.