Well done telling his sister – I know how hard it is to tell others – it is good that his secret is being blown in the areas where people care.
You don’t have to answer this but if you had made a group this week I would have asked you if you still love your husband. Love means different things to different people I know but reading between the lives of your posts I believe that you want to save your marriage while preparing to accept that it cannot go on in its present form.
I live by a simple adage now and that is that ‘I will never live with the addiction again’. To me that is not turning my back on the person who owns the addiction but is standing shoulder to shoulder with them. I have been in recovery from living with the addiction to gamble for 8 years – I knew 8 years ago that I couldn’t do it anymore and that knowledge gave me the strength to change the one person I could change – and that was me.
The addiction is probably causing your husband’s depression not the other way around. My suggestion would be to tell him that you will support him while he seeks help.