I haven't read your sitch yet but I sure don't like the sound of your last sentence.
If you truly feel you're that close, please get in touch with a suicide prevention hot line.
One thing I can assure you of and that is most of us have had the same feelings in the beginning. It is called spinning and that's exactly what you're doing.
Do not expect yourself to pull out of this overnight. It didn't happen that fast either. Cut yourself some slack. Put your focus on you. DBing is about saving yourself first. Maybe in the process the M gets saved but that is not the first and foremost issue.
Take care of yourself first, then you can deal with whatever happens in your sitch.
You're not alone, we care.
The thing is that I've been feeling this way for months now, but today it got to be too much. Thanks a lot for sharing your wisdome. It helps to hear I'm not alone, or crazy, or just an idiot for letting someone or something feel so hopeless