Think about the air you breathe. You couldn't stop breathing, no matter who told you to, no matter who offered you whatever amount of money, no matter what. You need it to survive.
This is alcohol to an alcoholic. They forget how to breathe, they think they need the alcohol to survive. And the really sad part is, they do. Their brain cannot handle the withdrawal. No matter what anyone says, or does, they can't stop until they are willing to go through the withdrawal and realize that no, it's not the alcohol, it's the air they need.
It takes forever for them to realize it. Relapse will happen. You will end up back where you started. It does not matter to them. They get stuck. No one can get them out of their grave unless they do it themselves. Sometimes they don't realize it at all, and end up dying of cirrhosis or cancer or whatever. Either way, don't think for a second that there wasn't someone there for them at some point who loved them, and thought that love would be enough. It wasn't.