Do not beat yourself up. We all struggle and do slip ourselves in our recovery. Being the mother of an addict is so hard, even though it seems like it should be simple enough. But, they are our children and even though we know what we should do and not stand in the way of their bottom, we do make mistakes. I know I have, especially during this holiday time. However, even though I have helped my son, when I should have not, I do know, as it appears you are aware, that there is nothing I can do to make him stop using or stop making choices he has.
We too must grow stronger little by little. I have found I have taken 1 step forward and 2 steps back during this time, but at least I am not caving in on everything. Hang in there. My prayers go out for you and your sons.