I haven’t got long tonight but I just wanted to comment on the worry you expressed about becoming hard.
I think that unless a person shuts down a large part of themselves when they change from old behaviour to new then they will struggle to cope.   Life is scarily difficult during this period and building up resistance takes all your energy.   Five years down the line, or even a lot less, you will feel compassion for others again because you were compassionate before although maybe it will show itself differently? 
I feel compassion every time I read another new post but I never cry for members as I might have done a few years ago.   I know now that the addiction to gamble can be controlled but more importantly, I believe that every member of this forum can move on and live a life without the addiction wrecking it – not only that, they can if they allow it, take the experience and make it into something of value.  
I get a far greater boost out of people overcoming difficulties in their lives than I ever did before.  I feel it is easier to praise to people than I did before.   I think that crying with others, although done compassionately, didn’t really help them.  I think being strong, not hard, helps others and that to me is compassion.  
Do I get impatient?   Yes of course it can happen – I want things to change sometimes before people are ready but then I remember how long I took and realise that I should be the last one to judge..
I am concerned that you are feeling more stressed because you are acting as a buffer for your CG.    I do understand and I cannot tell you what to do but he does have to learn to cope with some stress without using it as an excuse to gamble.  I am sure you are very aware of what I am saying though.