I should clarify that I am not a professional anything, but have been in similar situations. I also wanted to say you sound like a good friend, please don't ever forget that, whatever happens.

This situation is tricky because you could end up getting hurt yourself depending on how things go and how involved you get. It sounds like you are already suffering.

Here is what was said in a similar situation that I have been in: "I care about you and want the best for you, but if you mention plans to harm yourself I am calling the police. Otherwise I am happy to support you and be your friend." It is terrifying and difficult to say those things and believe them and be okay with the results. It could mean the end of the friendship. It could mean giving up the results of your friend to the universe.

Whatever you end up doing OP, a stranger on the internet is rooting for you.