Your situation is a difficult one at best. It is very difficult to dig yourself out of debt. It requires a total committment to not spending. Easier said than done.
Being supportive in a relationship is a two way street, hence, it is not all about your being supportive of him, he too, needs to be supportive of you. You seem to be over analyzing his issues.
Your first priorty is getting your finances back on track, for your children, to keep a roof over their head.
As for your hubby, this is his problem to resolve, he has an addiction that is hurting the entire family. You are showing your support by trying to keep the family finances in check. If you cannot express your feelings and concerns to him there are more issues than just spending.