[CW: addiction] Interventions for pre-psychosis in an meth user I know?

So I've known "B" over a decade.

She's lived a pretty rough life, as you tend to if hard drugs are at all an attractive option for escape.

I last saw her at a local pub shortly before emigrating to work over the summer where the interaction would be best simplified as a "crashout" over a moderate severity gaffe I made.

I put her in touch with "L" recently, one of my closest friends, and a mutual from high school.

This morning I asked how it went, and I was deeply saddened to hear the report.

B was incoherent about a quarter of the time, and when I came up, B was clearly still deeply upset over what had happened when we last saw each other. I had expressed that I forgave her in our ~weekly phone calls since then, but the real revelation was that when L and her went back to B's place, B pulled out some meth crystals and asked L if he wanted to snort some. L declined and chatted with B while she spun down into the sunrise.

For the past few months since she started a college program, B had mentioned some pretty severe insomnia. With the additional context I feel confident to say that this is just the negative effects starting to pile up form a habit that has been going on a while.

My primary concern is what, if anything I can do from the opposite side of Turtle Island without inducing a feeling that some of B's only friends are "conspiring" against her.

I thought of sending Magnesium and B12 supplements with some of my disposable income, but I doubt that is all that can be done. B's self care is clearly slipping and I feel there's seven weeks or less of this left before a psychotic break happens.