Everything your husband is saying is just what alcoholics and gamblers in the throes of their dysfunction say when someone theatens to turn off the tap.
The fact that he reports that his counsellor, friends, family etc. totally validate his behaviour and condemn yours shows that he is twisting your situation and manipulating others by maligning your character so as to shirk the blame and need for improvement that rightly belongs to him.
It proves that he is firmly invested in victimhood, and has no interest in changing - this is why he is not only lying to others about his problems, but to himself: he has no interest in self-accounting or taking personal responsibility of his mistakes and making changes.
He just wants you to keep the tap on.
He doesn't necessarily see that as dragging you and your child down - he's the victim of you, circumstances and the universe, afterall - but that doesn't change the fact that he inexorably will.
The thing is OP, he's just not ready to change. To be open, honest and accountable. He's just not. Maybe, awful as it is to imagine, he never will be.
And as hard and unfair as it is, there is absolutely nothing you can do that can 'make' him ready. That's just not how dysfunction, addiction or personal growth/maturing works.
What I can say is that for many people in his situation, losing their significant other/family can be the wake-up call needed for them to finally start the years-long process. Of course, many don't, and just find a new person to vampirise.
But that ifls not why you should leave (though it should somewhat ease your misplaced 'guilt' aboit leaving).
You should leave because you deserve openness and honesty.
Because you deserve someone whom you can rely upon, who protects you, your family and the life you build together by holding himself accountable to ethical and behavioural standards.
Because you deserve to live without a potential axe constantly hanging over your head by virtue of your legal and financial entanglement with him.
Because you deserve to live in relative freedom, instead of having your and your child's future and opportunities continually hobbled by a husband that recklessly drains your resources and limits your opportunities because he's far more interested in indulging his dysfunction than doing the hard work so that he can thrive with you.
Because you child deserves at least one parent that models healthy behaviour and relationships for them.
OP, how would you feel if your child was in a relationship with someone like your husband?