I just read your post where in the comments you explained why your wife is back in jail and I just wanted to say forget my comment above because after reading the story I think this is a different situation. (I should have read the other post first before giving a response, sorry).
You're wife came home at a bad time and wasn't prepared for handling life under those not usual conditions. I am a recovered heroin addict and I know that 3 close deaths in that short of a time would really test me and I haven't been away from society for a very extended period of time. In fact, she handled it extremely well and set up help for herself. I would def. give the testimony, expecially based on how she did all the right things after using.
Do what you feel is right, but I just wanted to make sure I wrote a response that more accurately speaks to your situation. Normally I would give the advice I wrote in my first comment, but this is not a usual situation.
I hope everything works out