"Dear Dr. Dennis,
I was just wondering what is the success rate for an ex-heroin addict who has been in rehab for 6 months? He has half custody of our children and I worry everyday that he might relapse! He drives my children around (and has while on heroin). I should not live like this, I am young, I am in college and now that he is out my grades are dropping. All I do is worry now -- what can I do?"
The best thing you could do for yourself is get support. One of the ways to do that is to go to Alanon or Narcanon and work the steps with a sponsor.
This would be for you and your recovery, regardless of whether or not your children's father is using. One parent in solid recovery is much better than none! You can make a decision to get the help you need and to step off of the roller coaster that addiction brings with it.