Hi, Rhode, and welcome to SR. I'm so sorry for what brings you here, but am glad you're reaching out to ask questions and get support for yourself (and by extension your children.
Originally Posted by
Rhode 
(BTW – at what age would they understand that mommy has a problem?)
DS was 3 when I left XAH. Did he completely understand the nature of alcoholism? No. (Do I? No.) DS though did know something was up, that something was not quite what it was supposed to be. He saw his daddy's walking become staggering, he heard the slurring in his words. He saw his daddy pass out. I never, never, never what to see his face like that again. He came running back to our room crying and scared and said that "Daddy is sick like Goldfish" (Our goldfish had gone belly-up not long before.)
XAH had been able to 'hold his liquor' and hide his drinking well for a while. His drink of choice, BTW, was vodka, beer if he wasn't hiding it. It's part of a stage of alcoholism - increased tolerance. But the day came when he was no longer to hide it. DS saw it at 3. Kids take in and know so much more than we give them credit for.
The book Under the Influence helped me understand how alcoholism affects a person and how it progresses. (There are excerpts in the Stickies.)
It’s hard to watch the other parent of our children spiral down. As Lillamy noted, each person has their rock bottom, and that applies to us as the loved one of an A as much as it does to the A. Related to XAH’s alcoholism, mine was finding a picture DS had taken with my digital camera of XAH in the tub where he’d fallen and looked like he should have been passed out hours before the picture was taken. That was it, I was ready to leave. I saved part of my paycheck in an account XAH couldn’t touch and then used it for a security deposit for an apartment. XAH’s bottom? I don’t know. I don’t believe he’s reached his yet. It has not been losing his job(s), losing his truck, or even losing his family…
Wishing you peace and strength.