Hi Mel,
This is a hard post to answer. So I'm going to take points as they come up. It's a tough letter, but nothing is meant to be judgemental. Not everything is say is necessarily about you. And I mean well.
First thing is, cop to owing those utility bills. You used the power, you owe for it. To fight about whether or not you do makes you look dishonest. So establish your honesty. Also tell him what's going on and why you can't pay. A lot of landlords know about other ways rent can be paid. Agencies that can help.
My mind is a sieve for details, so I hope someone else can tell you about possible agencies.
Hitting. It's great that you aren't allowing yourself to be hit, especially (but not limited to) in front of your son.
So what next? Are you going to let him back, either out of affection or monetary need? Most women do. I think the average number of escapes from an abuser is 13, before someone finally gets out. When you're ready to commit to re-building your life, you will do it. If you file a restraining order, there's about a 10% chance it will make him more violent. So committing to leaving will be a whole change of your life. It's OK to try to leave and fail. Just try harder next time.
Until you're ready to make that complete change you will be stuck in problems like the one with your landlord. So you need tactics to survive within the situation. You must develop some autonomy, including finding a way to earn some money. Even if it's not enough to live on but gives you experience. You might work daycare, which pays little, but allows you to bring your child, and gives you work experience. Do you have other work experience? Is there work you could do from home?
When you are ready to make the huge step to leave, there will be different questions and solutions. At that time, you should go to a specialist. Go to a women's shelter. They also have long term housing. And they have great connections. Family centered services. Vocational rehab. Child services. I don't know the agencies, but there are a lot of them. And they will work with you instead of working against you if you ask for help.
Some of the things that might be required of you for such help include: Abstention from alcohol, etc, because even a little will get peoples' backs up. Some therapy, because most abuse victims need to address co-dependency issued to heal from victimization. Job training. And very often you have to give up things. Like furniture and stuff that keeps your from being fit into a place of refuge. You'll need a new definition of humble -- which means not to claim to be more than you are (like above help, etc), but also not to claim to be less than you are.
There is light at the end of the tunnel. I found it. Others here have found it. It's never easy, but lots of people can gotten through that tunnel.
Meanwhile, how can we help you?
Tina