I'm so sorry to read this. I've been there.

I know that you don't want to be in this situation and it's very emotionally taxing. Just keep working your way towards financial independence in the meantime. Keep chipping away at it. You will get there -- I did. And then you can do whatever you want.

You may never get the money he owes in child support, but you WILL stand on your own two feet one day.