How do you get over a deadbeat?

As a single mother, how do you get over the pain of the father of your child not being a part of his/her life? How do you move past all of the excuses...all of the lies? Most importantly how do you forgive yourself for choosing this person? I find myself looking at my son and crying for him. Not because I see his father in him (he looks just like me PRAISE JESUS), but because his father is absent in his life and he is missing out on the greatest miracle known to mankind. From day one it has been excuse after excuse and lie after lie. Yet and still...I have held on to the hope that he would come around and be the father that his son needs. But no...its still the same old bullshit that its always been, and now that my son is actually here it hurts me even more. I don't understand how he can get up in the morning and live with himself knowing that he has a child that needs him. I don't understand how he can go on with his life and think that he can keep his son a secret. I look at my son and for the life of me I can't get how he could deny his own flesh and blood...his first born son...his "legacy". It causes me a pain and a hurt that right now I don't know how to get over. So many single mothers have done it in the past. They find the strength to do it for their children. My mother had to do with with my father. I wake up every day and I find the strength to press on for both me and my son, but I want to know when will this pain go away? When will the hurt finally subside? When will I finally be able to accept that the father of my son isn't going to be there and is not worth the time or the effort I have been putting into him?