Wow! I don't know your H, but what I gather from your last post... what a JERK!!! He doesn't want to stay home with his sick son b/c its "not his responsibility"? WTF?
I say go dark. You need to start taking care of yourself. Stop worrying about what's going on with him and worry about what's going on with you. Going back to school is WONDERFUL!!! You don't need his approval or permission to do so. Keep doing things for yourself and your son. Its hard, I know, I've been there... but if you keep at it, even one month from now you'll be in a much better place.
I think you should ask yourself before you tell him anything you are doing for yourself... like the school thing. Ask yourself what kind of reaction you are hoping to get from him? Then ask yourself what is the likelihood, based on his current behaviors, that you are going to get that reaction? If that answer is slim to none... don't bother asking. You are just setting yourself up to be disappointed.
When you are happy as an individual, you are in a better position to determine whether a partner enhances your happy life or weighs it down.