Marisa,
the ball is in his court. He is an adult who has been informed by health professionals on what HE needs to do to survive.
You need to step aside and let that happen. I know it's hard. I watched my X turn into a ghost of his former self due to drug and alcohol related illness. He knew what he had to do. He chose not to.
Oh well, not my business anymore. At some point you just have to stop worrying about it for your own sanity. I did and I am a much happier person for it.
You deserve that too. He is not a child. He has to man up and save himself.