i think that it maybe really time for you to stop right now and breathe, NONE OF THIS IS YOUR FAULT. we have 7 kids and i had the same concerns as you, you can now do what you need to do to protect you and your kids, its never too late. my counselor told me once about my kids when i was so scared that they would be scarred for life, he told me that as i got better, they would too. i found that to be mostly true so far. today i have 5 grown kids and yes i do see some codependance in their adult lives today, but i can't change what happened in the past. i did all i knew how to do, giving the circumstances. i took them to meetings and counseling and i had to decide to make a better more stable life for them even if i had to do it alone. i don't know yet, if any of them are addicted but i can't continue to worry about my past, its what i do today that counts for me. all that i can do is set an example.
again i say, it is not your fault or your responsiblity to take care of nobody but you and the kids. nobody is saying that you have to leave your husband, all of the time i didn't leave mine, but i decided what i could and would not live with and made a decision to stick to what i said, the rest was up to him.