It is not that simple in today's tepid economy. Also I have seen right here when WASes have A's with their work colleagues and ended them while still working in that same workplace thereby restoring their marriages.
Ideally, we would prefer that MDU's H take concrete steps to move way from the OW. Even if that does happen, it will be a while to seek a job that is comparable to his job and pay scale. That process just doesn't happen overnight.
Even if this isn't an option, people have SUCCESSFULLY ended their affairs with their work colleagues and continue working together.
We just need to work with what is in front of us in MDU's sitch.