I agree with love love... . Consider the suicide message a gold star for you ability to go NC for so long

. It bothered him so much he had to pull out all the stops. (If the threat was real that is serious stuff, he may be in pain, and may even be having those thoughts in which case he should be somewhere under observation, but odds are it was just a tactic to reel you in).
I hear you having mixed feelings, AND you noticed how manic he was... . that is all great stuff. I hope you directed him to professionals for his state of mind. It certainly is not your responsibility to take that on.
My therapist told me that a relationship is for the majority of the time supposed to be a positive experience... . no an insane roller coaster ride. I realize that I did not know that when she told me? That also meant that I was part of the problem. Why was I picking/accepting these individuals for relationships and why was I staying/attracted to the chaos?
Sounds like you are sorting it out... . Try to move forward... . stay away from the sick one and work on making you better better.
I know the siren sings... . why are we built this way? LOL!