I'm going to have to disagree with Cobra. While I'm not sure war is the right term to use, blazingly aggressive defense of your kids is in order. Think nuclear bomb rather than Operation Barbarossa. She needs to know that under no circumstances can she play R games with your kids. Who cares if the threat is hollow or not. Frankly if I were you, I could also care less about whether or not she would think you were weak or whatever if you did nothing. What she is thinking, what she might think, what game she might be playing ... who cares. The only strategy is it stops right now. This is your child, you defend with your life if necessary.
Maybe I and others are just blowing this out of proportion. Could be. All I did was imagine someone saying the same sort of thing to me that your W did to you. The rage came rather quickly.
Its not that the threat she threw out there was particularly frightening, I'm sure you could figure out a way financially around it. Its the fact that she would even think for a second to threaten your child.
Not trying to one up you or anything. You are dealing with stresses I have no experience with. Trying to make it all stay together and sane must be bewildering and I admire how far you have come.
Good luck to you and God bless (if you are so inclined).
Chrome
"Recollect me darlin, raise me to your lips, two undernourished egos, four rotating hips"
