As my therapist once told me, "It's about behavior, behavior, behavior." Since your AH doesn't have much to say (we must have married twin brothers), you have to go by his actions. He's a bit apathetic, to say the least. And I completely agree with Denny on this one. You married this man and had children with him. He should be pulling his weight, whether he wants to or not. That includes giving you financial assistance with your children.
By taking on all the financial responsibility, it seems you are still enabling by letting him off the hook. As painful as it is for you, I think you would be much better off by ending this relationship. Waiting for him to make amends, see the light, and become the loving husband you need sounds like an exercise in futility. It doesn't appear he is going to morph into your expectations. Hanging on to our lost dreams is a type of denial. Letting go is always painful. But you can't make him something he either cannot, or will not, be.