Well, since you mentioned mania and depression, it could very well be she's in the midst of a bipolar episode and that it has nothing to do with the suboxone or any other drugs. Would she agree to go get a mental health evaluation?
Many people who use drugs are self-medicating for one reason or another. My ex-husband was constantly drinking and drugging, mostly in an effort, I believe, to feel normal. Once when he was so wasted and really acting crazy, I convinced him to go to a well-known hospital that deals with dual-diagnoses. There we found he had so many different drugs in his system and the amounts were so high, they couldn't understand how he was still standing up. Even with them trying to sedate him, it took hours. But he was diagnosed as bipolar. Unfortunately, he checked himself out AMA after several days and to this day still hasn't had it treated.
Bipolar is a serious illness and can be difficult to bring under control. If you can't get them to get an evaluation willingly, if they're doing things considered to be a danger to himself or others, you can have him admitted against his will.
Good luck.
Hmmmm, that sounds very strange. Are you sure she is actually taking her Suboxone? That is certainly strange behavior, the only thing I can think of would be maybe she is selling her Sub for illegal drugs? Or is she having a hard time dealing with life off drugs? Were you friends with her before she became involved drugs of any kind?