Hello and welcome, so glad you are here, it is very hard to love someone with all your being and have them love you and complete you, yet be so irresponsible and careless with the lives of others.
Therapy has been a tremendous benefit for me, I caught my first wife cheating and when I confronted her she just moved out, if not for therapy I would have eaten a bullet. I went back this time becuae I needed to detach from my alcoholic mother and enabling father.
If it's any consolation, I think you did the right thing, my ex wife was like a drug to me, I did not believe I could survive without her, but I did survive, I moved on, I grew a little more every day, and met a great woman, I struggled to get used to a no drama relationship, I was always looking back, that was a nearly fatal flaw, I hope you don't make the same mistake.
If you would like to talk, I will be glad to listen, if you need a hug, just ask.
You sound like a nice person, your new boyfriend sounds like a good guy, your old boyfriend sounds lovable, but dangerous to himself and others, I hope he gets help before he kills someone.
Big hugs and best of luck,
Bill