I've known people who chose to die by their own hands, including one who jumped off a bridge to end his life. I found this book by accident while I was checking on titles for a client. It's about a man named Kevin Briggs who is known for talking suicides out of jumping off the iconic Golden Gate Bridge. There's a video about him on YouTube, or you can get the book here.
I write urban fantasy, and in my fiction there are "protector" characers who have a calling to help humanity. It's not often you ruin into one of these people in real life.