As a parent, you do the best you can when your children are old enough to choose where they stand on right and wrong, good and evil ... keep loving, keep praying, and do what you can do. Addiction means someone is trying to cope with deep pain, and it looks like both your children have lost things they felt should not have been taken from them. That loss of control, and sometimes the anger with God about it (because none of us really have control of our lives) is something every person has to come to terms with for themselves. You are showing them the patient love of God through your love of them ... it is still their decision as to what to do with that revelation, but you are doing the best thing you can.