Sorry the family is so useless .....grrrrr. (Fwiw......technology for a blood sugar monitor that doesn't involve a skin prick is just a few years away).
How is your H with her? Is he trustworthy enough to be left with her? If not, then sadly, staying in the marriage may be safer for her than unsupervised parental visitation in a divorce. I know a couple women with gluten sensitive children who can't get their ex's to follow the gluten-free diet when they have the kids.
I don't trust your H as far as I could throw him, and I think you do need to keep a Plan B in mind. Nonetheless, if the best outcome is H actually recovering from his addiction and the marriage being repaired, then I suggest you set the expectation that he be truly working on his problem. Show him what the path back to you looks like: meetings at least once a week, several phone contacts per week with his sponsor, complete transparency with his phone, email etc. I also recommend for you the Alanon book The Courage to Change.
Also, you need a support group of other moms dealing with this disease. Make sure you take advantage of any online groups; parents will be your best source of practical advice.
Lastly....know that none of this is about you. He's an addict. You didn't break him and you can't fix him. He has to be willing to do the work.
As best you can, pay off debts and squirrel away savings, some of it hidden so that if he does take of suddenly, you can get by until the courts make him pay support.
As for your feelings towards him.... they will probably come back IF he does the work.
