I know just what you are saying. The first thing I started to do is set limits. I do not go to the shop for my husband any longer. I live in a very small town. I found my self getting embarresed going to the store every few days buying a liter of vodka. I started to rotate the three main strores in my town hoping they wouldn't notice. I finally stopped. I told my husband that I get embarressed and just would not do it any longer. After a few times like a child he just stop asking.
I always call in my husband rx's for his refills and will always pick them up. This week he says to me "I have not taken my rx in a days because you have not pick them up for me." I said there is no one to blame but yourself and maybe it is time you call and pick them up youself. I advised him that it is not my responsibility. I said in a loving way and not in anger.
There are somethings as mothers we just have to do to keep our house going. We have to fix dinner but do not have to serve them there plate! It is very sad and unfair that we have to take on so very much. We are getting stronger and they are getting weeker.
Make small changes and you will begin to feel a litter better and in more control.
hugs
nand