Sorry for what you are going through. Only you can decide whether it is your bottom....
Those poor children of yours don't have a choice though. Where do you want to be in five years? (I hate this interview question but it popped into my head in a right moment and saved my life)
I hit my bottom when I had to take incoherent XAH to rehab where he escaped from eventually.
There is much better life out there for you and your kids.