Hi GUM,
Please feel free to unburden yourself on here whenever you want to. There is always a "listening ear".
Re this comment from on of your postings":-
"But he wants to solve it on his own".
Ah yes, that one. A triumph of hope over experience methinks. He cannot solve this problem on his own; alcoholism is an illness and he needs to treat it as such with proper medical help.
He needs to seek proper help (not attempt to stop drinking on his own because that will fail; also on medical grounds just stopping drinking altogether is not without risk) and do this without either you or the children around. If he is serious then he needs to get onto a properly controlled detox program with counselling to work through why he drinks in the first place, the triggers for doing same. He made and has continued to make a conscious choice to start drinking.
You can be equally supportive by not holding his hand or sharing the load of responsibility, he needs to do this on his own.
What does you Mum think?.
Even with the above measures in place (and this would give you some indication as to how serious he actually is about addressing this illness) there are no guarantees and he may continue to drink. He will have to undergo a complete sea change of attitude and forego his old friends (many of whom doubtless are his drinking buddies).
You and your children are your utmost priority now; not him. He is old enough to make his own choices.
Gold star to you for seeking help for your own self following your Dad's passing. I wish you well with this, keep at it!!!.