Hi cantdeal, I can well understand how you'd be at the end of your rope. I'm not clear on whether your husband and you are living together or not? His behaviour is disgraceful either way, leaving you to look after your son on your own.
Can I ask if you have any family support locally, either from your side or his? If your family doesn't live nearby, is there an option for moving closer to them? There may be other support you can draw on to help your situation. Your husband should be contributing financially to allow you to pay for necessities. If he isn't, is there legal aid available to make it happen?
I'm sorry for the stress you're under, and I hope that posting on SR will help relieve the stress and possibly provide some useful advice.