Has she ever been diagnosed with anything? I mean besides substance abuse? Some of the things you mention sound like there is more to it than just substance issue. Is she seeing a therapist? Psychiatrist? I’d also say that 8 jobs in one year isn’t a millennial thing in my experience. It sounds like she needs more professional help. Understandably there is nothing you can do. We have somewhat similar situation with one of my stepdaughters, she is older though.