I’m afraid that no amount of worrying if he ‘gets it’ make any difference – it will only wear you out more.
He won’t see what he has done to his life because as yet he can’t afford to look.   To look would be to see and if he sees, he will know what he has done and if he knows what he has done, he will have to take responsibility for his actions and that takes such courage.   If your husband goes to GA , I hope he will be in a good group and that they will help him take his blinker off and face his demons – he ***** the right support to help him move forward.  
I would never ask that you block your loved one out but you can refuse to live with his addiction and mean it.   By taking care of yourself you are giving him the best support possible.   He will not have wanted to bring you down but his addiction will take you all the way if you allow it and then you are part of the damage he has to fix. 
He will need time to come to grips with what he has done to you and the children if he is to live gamble-free.   Unfortunately those who love CGs cannot make their loved one stop gambling – other CGs, dedicated counsellors and GA can do that – they can understand your husband as you and I cannot.  
It is not ‘walking away’ to look after you and your children first.  Your husband is unable to take responsibility for you all and it falls to you, to support him by doing so.  
I have a group in an hour and a half and maybe you could join it and we could communicate in real time.   I am going away tomorrow and will look for you on my return.  
I don’t know if you know the Serenity Prayer which we say in the last 5 minutes of our Tuesday group and which your husband will say tonight if he goes to GA.  It is
God grant me the Serenity to accept the things I cannot change
Courage to change the things I can
And widom to know the difference.
I also like the other version which is
God Grant me the Serenity to accept the things I cannot change
Courage to change the one thing that I can
And wisdom to know it is me.
When you have tried everything else and it hasn’t worked – it is time to try something new.   You have almost certainly have been putting your husband first for a long time and his addiction will benefit from that – support him by looking after you.
Hope that makes sense but please keep asking questions – you will find your balance and with knowledge you will be able to make informed decisions.