as much as the ethos "do no harm" goes, you're still not her therapist. and it's not your fault if you choose to go.
it's my take that it may be nice if y'all can pick a time to sit down and talk about it. I don't think it's entirely comparable to what me and my ex did, but she knows I'm a chronic relapse so we wrote down every possible outcome or impact my active addiction could have, what her boundaries are and how far I can accept her interventions to go, and when/how we can back out before one person burns out.
we agreed that only accidental ODs be reversed. if I make it clear it's intentional, no questions asked. no cops, 911, naloxone, none.
she backed out before the downward spiral. that was a case of effective damage control.
after all I can't deny that your existence may very well be what she finds meaning through or latches onto. but we're to wish the very best for everybody, and it's not impossible for y'all to process why this is in your best interest, and help her transition from this relationship. I think it's worth discussing her suicidality as well. her reasons to die and to live.
devastation is not the same as becomimg fully committed to suicide. if she wants to live, she will. I've had too many friends pass away from overdoses, but, life goes on.
communicate. that's some of the best things people can do for each other. and I wish you the best.