Certain people's answers are always going to be, in the end, show her who's boss. So I have nothing else to say.
I can only speak for myself, but that is not at all what I'm trying to convey as the basis of my hard-line approach.
My basis is the concept of treating infidelity primarily as an ADDICTION, and -- as such -- that one needs to remove the addict from the source of their addiction, by whatever means possible, and that further contact with that source will greatly set back their recovery.
There are certainly other schools of thought, and mine isn't even necessarily that "DB" (altho I combine it with DB concepts and techniques like "180s", "GAL" and such). But if all you read into it is "show her who's boss," then you're clearly inferring what I'm not implying, and I think it's coming more from your own sitch than it is from anything I'm recommending to H4U over the past several months.