Most Helpful Guy
I'm 11 years sober, and I think you're realizing his bottom could be a long ways away, even if his life is turning more and more into shit as it currently is. Everybody has a different threshold that may make them realize they need to want to help themselves or they'll die alone and miserable.
If he loves you, like you say he does, and doesn't care about himself, then I think the only thing you can do is tell him you will not wait around and watch him kill himself, and you'll have no choice but to leave him; and you better be prepared to mean it and exact on it if he blows you off.
You can explain if he gets help, you'll be there to support him in his recovery and learn more about his illness so you will have better ways to handle situations like this (Al Anon would be great for you). But, he needs to want to get better for himself as well as for those people he loves, or his attempts to get better will fall flat on their butts.
Most Helpful Girl
Without Him even admitting he needs desperate professional help here, dear, there is nothing you can do for him. Many times over, someone who involves themselves in someone else's life who has these problems of strife, end up to Be----Enablers.
You need to stop Enabling him to make it easy to continue. If you love him, talk to someone in helping you get him help so he doesn't think you are always there to... Pick up his pieces.
If you don't feel you can be of any help with this, then keep him at arm's length, away from Harm's way and this would be... your heart that will always get broken every time he Continues "Getting worse."
Good luck. xx