I did buy the book you guys recommended and am a bit confused by the advice. Dobson recommends an ultimatum - choose marriage or affair. Most of the advice ive seen here says no pressure.
Which book, Love Must Be Tough? It's not completely consistent with DB'ing. The DB'ing approach is not to pressure the WAS even if they're involved in an affair. That doesn't mean to be a doormat, it just means don't pressure them with constant R talks and such. MWD talks about an ultimatum in DR, she calls it the "after the last resort" technique. She says if your spouse has refused to let go of their affair partner after you've done everything else and if you're just done with it all, then lay the ultimatum on them. But she warns not to do it unless you're fully willing to accept D, because that's where it may lead. I think that's the difference, in DB'ing the ultimatum is the last resort while in Dobson's book he presents it as a tool to "wake up" the spouse. I think MWD has it right though, if you push an ultimatum too soon it'll often force the sitch into D.