Well, that kind of stress on you isn't good for your child, so you've made a good first step for you and him by reaching out. I have to say, good for you, too many people don't even get that far.
Do you have a way to get out during the day, say to a park or playground? Could be a good way to meet other mothers out with their children, and that'd be a real good step towards developing a social network--which, frankly, it sounds like you need.
When I was in your situation--spouse at work, me tending the kids--I didn't do a very good job of making sure I had a life outside of that, and the whole family suffered for it. I hope you do better by your family.
Feel free to drop me a line anytime if you want to talk.