(((hugs)))
Threatening suicide is classified as domestic abuse. And I think you are absolutely right -- you can't trust your children with an A as their caretaker. If he was anyone other than your husband, you would know this. You would never think of leaving your children with a daycare provider that you knew would be likely to drink. And believe me, I'm not chastising you; I spent 20 years with a man who would pass out drunk when he was supposed to be watching our children...
Someone said something here to me that really rang true to my ears: That the marriage vows don't just have the "for better for worse" but also the "to have and to hold, to love and to cherish" -- and in most cases, alcoholics have broken that part of hte contract long before their spouse decides to break the "til death do us part" part.
I don't know if you're ready. Only you do. But I do think you have a great opportunity, if you are ready, to set things in motion right now. Will it be messy and hurtful and ugly? You bet. The question is -- will it be less messy and hurtful and ugly than staying?
Hang out here and talk. And listen. And vent. There's a slew of great people here who have been through the wringer and who know what you're talking about.