I will try to tell you my experience and maybe it will help you.
I am still trying to work through my feelings from my AM's overdose and attempted suicide that was almost a year ago. I didn't see it happened. I got a phone call that she was unresponsive and on the way to the hospital. For awhile, I didn't know whether she was alive or dead. It was a very scary experience. Some of my feelings were so extreme, that I wasn't able to feel them all at once. Also, I have fear that she will attempt it again.
In my mom's case, her caregiver alerted the authorities that my mom was not answering the phone/door. The police broke into the house, and the paramedics rescued her. She received treatment at an ER, and treatment at a psych facility. I believe, of course, that everyone who saved her did the right thing. I made lots of phone calls to the hospital to talk to her caregivers. I don't think that I overstepped my boundaries. This was an emergency, and she could not do these things for herself.
I draw the line at doing things for my AM that she could be doing for herself. I won't send her money. I won't give her medical advice about how much meds she should take. I won't be her counselor. I won't listen to her if she wants to indulge in negative thoughts. I will talk to her about positive things. I will send her cards on holidays. I will not bail her out of jail. I will attempt to commit her to a psych facility if she is being dangerous. I won't call her back just because she left me 5 messages in a minute. I will call 911 if I feel she is unsafe.
Those are the boundaries that I have worked out for myself when it comes to dealing with my AM. My boundaries could change at any moment. They are for myself and my sanity (not for her or to fix her).
I hope that helps.