He's lying about it and bingeing. He is an alcoholic. I'm sorry. I lived with one for a time (an ex) and I know these are two big signs. So is getting moody when going without. Can you try to get him to a GP? A liver function test might be the wake up call he needs or a chat with the dr might help him to realise there is a problem.
Alcoholism can have devastating consequences, it's best to act as soon as you suspect something. BUt there is a very good chance he won't cooperate as he won't want to hear it. Any chance of getting him to couples counselling?