How do I break up with him?

We’ve been together for 8 years and have two kids and we live together, and I have no where else to go. But he’s an alcoholic and even though I have talked to him multiple times about how needs to get help, nothing changes. He doesn’t respect me or my boundaries. He doesn’t help me at all, he just sits outside all day and drinks and smokes. I just can’t keep worrying about him, and hoping he’ll get his shit together and stop acting like a child. But I still care about him and want to co-parent & hopefully remain friends, because deep down under his drinking problem I know he’s a good person he just needs to get his shit together. But I just don’t know how to break up with him, I don’t want him to guilt me into sticking around because I know he’s never going to get help if I keep enabling him. I just don’t know what to do, please help.