Like many posts of this type its mainly about him rather than you. What about you, you and your children matter here. You state that you've tried everything. Unsurprisingly nothing has worked and it will not work either.
Your H's primary relationship is with drink and his drinking is affecting all the family unit markedly. Your children cannot grow up thinking that all this is at all normal from their dad because it is not. His work may be unaffected currently but there are no guarantees here whatsoever. He could well end up losing everything and everyone around him and still choose to drink afterwards.
The 3cs re alcoholism:-
You did not cause this
You cannot control this
You cannot cure this
I disagree with your friend that you should accept this, she after all is not living with this on a day to day basis. What is happening here really is chaos and you are all lurching from crisis to crisis.
What are they learning about relationships from the two of you here, what are you both teaching them?. Did you grow up yourself seeing a parent drink too much?. I was wondering what you get out of this relationship now, what is and has kept you with him?
Hard as it is to read I would urge you to read the 3 act play that is alcoholism because you are playing out the usual roles associated with this; namely enabler, his codependent partner and his provoker. Co-dependency is often seen in such relationships and that in itself is a problem.
GP may well not be able to help when it comes to his drink problem because you are the one addressing this rather than your H. If your H cannot and equally will not address his drink problem (and that looks highly likely to be the case, many alcoholics are after all in deep denial of their drinking and badly underestimate how much is being drunk) then there is NOTHING you can do to help him. You can only help you and in turn your own children ultimately.
I would seek legal advice going forward and contact Al-anon, if possible attend their meetings in person. At the very least read their literature. Your children dependent on age may well benefit from talking to Al-ateen.