Let her focus on her crazy and you keep yourself and the kids away safe from her drama. Assuming you don't have to have her consent to leave the jurisdiction, I think you should stay put with the kids and if she ever gets herself together and makes the right steps forward, she probably knows how to find you.
I wouldn't assume manipulation. I just have to believe the disappearing from the kids act is harder on the moms. I'm sure that the pulling away from this addictive and escapist life is difficult and it will take her many missteps before she can do it. Just stop trying to be the life preserver for anyone but your kids.
