I am sat here feeling so sad for you, you are living my life before my husband stopped.
I too used to do all you say, hold the house together, its basically like being a single parent, but without the ability to live your own life. My days comprised of taking our daughter to school, working, doing dinner, bathtime, bedtime, then sitting on my own with my heart racing, worrying about whether he was coming home, wishing so hard that he would come home, but then if he did and he was high it would be a nightmare as I couldnt hide my sadness. Not being able to rely on him for ANYthing, never asking him to collect his child because he might have been high, never being able to make plans to go out for dinner with my friends because I didnt want to leave her with him in case he used.
Hiding it from people and making excuses for him constantly, its draining.
I dont really have any answers, my husband is now in his late 40's, and he developed a hole in his septum, I think that partly helped him stop, because if his nose had ended up like Daniella Westbrook's he wouldnt have been able to hide it from his family.
He didnt ever get into debt with it because he can earn decent money, and had people around him holding his business together when he was absent.
I used to worry that he was dead on nights out, he would go awol, he'd tell me 'i'm coming home now, i'm ringing a taxi... then 4 hours later i'd wake up at 3am and he wasnt home, then I wouldnt sleep, but I still had to try and function the next day.
My husband also cheated on me, but then became paranoid that I had, such a mess was his head. It was such an awful time.
I just wish I had the answer for you, If I had my time again i'd probably still do what I did, even though it nearly killed me.
I hated Christmas because it would be another excuse to go out. And of course I never got decent presents, just some money thrown at me because heaven forbid any thought could go into choosing a gift that meant anything.
Please know you are not alone, and we are here for you xxx