Heroine, I don't think anyone is saying that you should regularly harangue an alcoholic about their drinking despite what you seem to be implying. Instead, what we're saying is that the non-alcoholic typically reaches a point where the only sensible course is to emotionally detach and to turn ones back on the drinking.
Trying to maintain a relationship with an active alcoholic can be utterly overwhelming. Almost without exception I can say that we (that's "we" as in people who have been in relationships with alcoholics) have tried the support and kindness and encouragement tack. And, almost without exception, we've had our support, kindness and encouragement thrown back in our faces along with an extra helping of broken promises and blatant lies to our faces. And typically we'll get all that with a load of threats, abuse, aggression and vitriol to boot.
Living with an active alcoholic can be fucking horrific. Trying to get an alcoholic who doesn't want to stop drinking, to stop drinking, is futile, horrible and often dangerous. My ex physically attacked me once because I made the mistake of pouring the last bottle of wine down the sink.
Living with an active alcoholic and maintaining a long-term effort to try to emotionally prop them up and clean up their messes can drain you completely and leave you feeling like you're going mad. So much of your life and energy is taken up by them and the chaos and drama caused by their choice to continue drinking rather than to seek help.
One alternative is to realise that their drinking is their responsibility to deal with. If they choose to drink rather than to face reality then there will inevitably be bad consequences. I don't see that there is any long-term benefit to anybody in trying to protect an alcoholic from those consequences as, otherwise, how else will they see that they are fucking their lives up and that they need to change the choices they are making?
But I'll be honest - my sympathies lie more with those who find themselves in a relationship with an alcoholic than with the alcoholic. The alcoholic is the one who is making the choice to continue their drinking rather than to do something about it. And let's not forget that no-one has the moral right to insist that another grown-up stops drinking. The non-alcoholic's choice is whether he or she wants to continue being hugely influenced and affected by that drinking or whether to detach and leave the alcoholic to experience the consequences of the choices they are making.