does he think he has a drinking problem? Once he realizes how it's affecting all areas of his life as well as yours he may be more open to seeking help. When he reaches that point, you should take him to the doctor. They can give him medication to help, and detox from alcohol can cause seizures so it's wise to seek medical help. Once the alcohol is gone, he'll need lifelong aftercare. AA, individual counseling etc. It's not the actual alcohol that's the problem, there's a reason he drinks and that's what needs to be dealt with.
AA for him and Al-anon for you. Just like addiction, he is the one that needs to change and admit there is a problem.