The best course of action when anyone threatens suicide is to call 911. If it was a sincere threat, they'll get the help they need. If it was a manipulation tactic, they'll most likely learn never to pull that one again.
Good job identifying that your life has become unmanageable.
You admit that this has consumed you, and is wreaking havoc on your own family's life. Is that acceptable to you? It sounds like the answer is "no", and that's okay- in fact, it's appropriate.
What would your life look like if you set boundaries according to what is acceptable to you?