I'm sure you're not a bad guy at all and she is not bad either, just ill with a devastating disease.
It seems you are going to have to take charge and leave her out of the equation for now.
Her words of blame are just that. You might want to check out Al Anon or some other recovery/support group for yourself and your kids and learn how you can gain control of your lives again.
You guys are in that spiral being sucked into the black hole she has created for herself. My feeling is she can go there is she wants to, but you guys don't have to jump in behind her.
Good luck to you.