Peo...you are definitely not alone....as a matter of fact, there are thousands of stories, here on this forum that are similar.....
I hope that you will contact the authorities and have him pay child support for his son. His son deserves that much....and, it is his responsibility to pay it. Even if you don't know where he is....you can use his social security number....
Don't let him slide on that responsibility.
I hope you will continue to post, because we can help and support you, if you will do so.....