I have had many friends with DUIs. I remember how down they felt when it first occurred. They thought their lives were over. They felt embarrassed and ashamed.
But it is 5-6 years later and they are doing great. But it TOOK TIME. It takes a lot of time to forgive yourself but remember to keep moving forward. As long as you go in the right direction, you are going to be better than you were yesterday. You know that you want to be better for your son, and for yourself. I believe in you. Continue seeking help in online forums and finding a sponsor. Best of luck to you, my friend.