Can I represent myself in a custody case for my kids?

I can't afford a lawyer. I keep getting referred to "low income" attorneys but it's still outrageous!
I had my kids stay with their dad so I can find a stable place to live. Funny thing is, I used to own a house, I sold it for this guy. We moved into his mother's house(her and I never got along) and I got a job and started paying rent. His mother hit me when I wasn't even looking while I was holding my daughter. My daughter got clipped too! There was no arrest made even though I called the police and told them what happened.
Long story short, when I left, I was staying with my brother. My time ran out there as I was looking for a place because I was approved for a domestic violence grant. When I had to leave there I had nowhere to go and I had my kids. If I had to couch hop for a few days I didn't want my kids with me. So I told their dad to take them (back to that house which was probably the hardest decision I had to make). As soon as he had possession of the kids, he applies for state help and everything claiming to be a single father!
I have a job, he doesn't. EVERY paycheck I'm buying things my kids need. From the gate when this situation happened, I told him I will take care of them. Why wouldn't I? I have a job, of course I'm going to! So now because of the state help he's getting I'm getting child support papers sent out to me.
I broke off the relationship. That was the last straw. I broke up with him. I told him when I found a place, I'm taking the kids with me. When I broke it off, he stopped letting me see the kids. I'm their mother! I was the sole provider of my kids since they were born! He NEVER contributed anything! Nobody in that house has a job so he got that state help to put money in his pocket. I was already taking care of my kids, why would I stop!?
Now that he's not letting me see my kids, I got child support papers. I hope he didn't file them already. I don't really understand the papers very well, I need help filling it out. I've had consultations with lawyers, but I can never go further, I don't make that much money.
So much for long story short, huh?
My question is, can I represent myself? I want custody. I have a place to live now and I need my children. Theyre all I have! I know I'm a good mother, I live and breathe for my children. It breaks my heart I can't spend time with them like a mother should. I don't want to take away his rights completely, I can't do that to my kids, he's still their father. I just want my kids in my custody to insure myself that I have them. Do I absolutely need a lawyer? Will I lose if I don't have one?
Thank you for any advice.