My ex bf whom i broke up with is getting suicidal now? what do i do? feeling trapped!?

Ok so my ex boyfriend has always been super possessive and totally obsessed with me. It got to the point where I could see just how emotionally unstable he was. Texts all day even though he is at work, wants to keep constant contact,gets angry if I'm too busy to respond and says I'm the one yet we don't even know each other long! At first he seemed normal. Now he is turning into Rebecca from The Roommate. Totally obsessed. So I broke up with him last night for my own safety and sanity. But he found me after church today even though I was hiding away. Followed me to my home and cried and pleaded with me for hours that he will change. I told him you are scaring me , please leave. Later today I find out he told all of our friends about his obsession with me. Obviously he left out his controlling behavior. They now think he is sweet and that he should never give up on me if he wants me. So now he won't stop! He is obsessing again! Says he will not live without me and cannot lose me. What do I do please help? I'm trying to break contact but he won't let me. We are linked through so many people. How do I make him understand that he needs help? That I cannot be with him? That it is over without pushing him over the edge? I alo found out he did the exact same thing to a very quiet girl at church. She just had more guts than I did and saw through him from the beginning. She told me to get out now! How do I do that? Thanks in advance.