From my readings and hanging around here since June, I really don't think tough love and DBing are necessarily compatible.
Reread the chapter in the Divorce Remedy about the wife who put up with her husband living at home and carrying on an affair for quite some time (over a year? - sorry, I don't have it handy, but I think their names were Carol and Dean in the Putting it all Together chapter). Michele never once suggested that the wife give an ultimatum or throw the husband out.
So, yes, this would certainly be a last resort, especially if you are divorce busting. NewYorkSurvivor has had some good comments against this tough love technique.
With regards to the kids already being in a broken home, they may be, but as far as my kids or my family know, everything is AOK between my W and I. We haven't told them and we are carrying on as normal other than the fact that mommy is gone a little more often than she used to be.
