Barbdee,
Sorry to hear of your sons recent setback. Hopefully, from being at Oxford house, he has the tools to get him back on track.
I do remember that Bipolar being mentioned on the forums.
In fact, I know this because I had wondered aloud to myself if my oldest son is bipolar. (I still wonder)
I believe addiction is a genetic disease. With addictions on both sides of our family, our 2 sons had a 50/50 chance.