Dear Madge
CGs generally need to be smart to stay on top of the manipulation game although given time the addiction unravels even the highest IQ.   Unfortunately the addiction to gamble doesn’t give off signals like alcoholism or **** addiction.  A CG doesn’t fall over, there are no needles, no ***** and their eyes are not spaced out.    It is because of this that they are able too fool so many counsellors and therapists who have never dealt with this particular addiction.   A CG doesn’t set out to fool – it is part of the addiction that they are capable of doing so well but a large part of the blame, in my opinion, is the inability of those who ‘should’ understand and recognise the symptoms and who are totally untrained.  
Removing CGs from the environment where their addiction has flourished is, in my opinion, based on all the evidence I have seen, very good.    It is very hard for a CG to change their life when the everyday world around stays the same – removing them from that world allows them to focus their minds.   I think it is very disappointing to hear such negativity from people your husband has talked to.   If everything he has been doing for 20 years has not worked – it makes sense to try something new.  
Everything you have expressed I understand – the loss of a loved one is unbelievably painful but worse still is the loss of self because it takes away the ability to cope.   I remember being unable to sign my name without making an error, inviting people round and then calling it off, forgetting where I was going and what I was doing.   I was even tested for Alzheimer’s disease because I believed I was lost and I thought it was best to remove me from the world rather than inflict that illness on those I loved.  
Hold on to the knowledge that you are worthwhile, you are unique and you are strong inside.   Dig deep and know that you are still here, necessary to your children and you have an important role to fulfil.  
I saw rehab as a break for me because I had no hope in anything anymore.   None of us can ‘know’ what will happen but if we do nothing, then nothing will happen,   Rehab and CBT has changed lives and it changed my CGs and mine.  
I cannot know if it is true of your husband but many CGs are wrongly diagnosed as Asperser sufferers and it does make it harder for those who love them to know which way to turn first.
It is hard to answer your questions because we can only offer support – we cannot tell you what to do but I believe we have to have hope and worrying about what would happen ‘if’ rehab didn’t make a difference is a worry too many. 
Your husband admits he is scared to deal with the **** inside him and this is something that I don’t think we can understand but there are those who can.   There are skilled counsellors who can open a person up and let the **** out – but have the ability to close them again.   Your husband does have to ‘want’ to deal with the **** inside him or CBT and rehab cannot work – this is usually the difference between a successful controlling of addiction or not.   A rehab cannot make it happen – there is no magic pill – they do need the addict to be dedicated and determined and then they can work with them – I hope that makes sense.    
I came up against negativity everywhere in the doctors and counsellors I met but finally with the right counsellors in the rehab my CGs changed his life.  
I am not sure your husband can find the right place for himself but maybe you could.   Find out all you can about the hospital that offers a CBT programme.   Knowing what you know now maybe you can ascertain if they are the right place for your husband.
Don’t accept negativity from professionals – somebody, somewhere is the right person for your husband.  
Keep posting, keep talking.   It is an uphill struggle and you are right – the torture for you has to stop.  
I took my CG to the rehab.  I was told I was treating him like a child, that I was doing it wrong again – but I am glad I walked that last mile.   I feel from your post you can walk one more mile with your husband and as long as you want to make that walk I will hold your hand and walk with you.  
Yes, you have to look after yourself first.   Yes – if you don’t look after you, then you will struggle to cope but you have coped so far and you have coped well. 
The biggest weapon in the hands of an addiction is the mind of the victim.   Free your mind.   ‘Know’ that you are in control of ‘your’ life and that there is always hope.
You are not lost Madge.   I can see you as clearly as anything.   You are doing well – you are functioning – you are still here.