Unless they admit and willing to seek help there isn’t much you can say, each person I believe has a defining moment where they see how much damage they are causing to them self’s or there love ones, I believe my partner realise this when she was giving 6months to live.
Before this, just mentioning alcohol caused her to flare up and cause arguments.
Hope he comes to realise how much hurt he is putting you through.
You aren’t alone though this.