Oh OP, no no no.
Please do as others have said, and contact Al-Anon for support and advice.
The first thing they will teach you is the 3 Cs.
You didn't cause this
You can't control this
You can't cure this
You are trying to cure him. This is not the support he needs.
Firstly depending how much he actually drinks he can't just not drink again. If he has a physical dependency he will need medication and support - if he tries to just stop he risks seizures and other issues. He also needs tests to see what damage has been done. The alcoholic in my family had pancreatitis due to alcohol and now has diabetes due to the damage. She also has late-stage cirrhosis now after "falling off the wagon" many times (although she's currently still in recovery. Small mercies)
Secondly even if you get past physical dependency you will still face the mental dependency. Once he's not drunk for a while he will probably go through the "Just one won't hurt" stage and it's an incredibly steep slippery slope from a beer after work to a bottle of vodka a day. Very few alcoholics stay dry at the first attempt, I think the relapse rate overall is around 70%.
Thirdly, most alcoholics start drinking as a self-help for mental health issues or trauma. As well as not drinking he may need some pretty intensive therapy to keep him in recovery. This will be tough on all of you.
Lastly, you can't keep this to yourself no matter how private a person you are. You will need help and support. If you can't reach out to friends or a support group you may as well leave him now because he will drag you down with him.
I'm sorry if this seems harsh. I have had an alcoholic close family member for many years and it's been brutal sometimes. The lies are the worst thing. Sometimes you need to detach with love.
I wish you and your DH all the best, but I can't sugar coat this for you.