SR, its because the LBS is always the safety net... always...
The WS never admits it, but they want to keep the WS around as a safety net... while they press the boundaries of the marraige gradually and watch the LBS fall apart. As long as the LBS shows a willingness to BE THERE the WS is going to explore the affair further and further.
Think of it like a high wire act in a circus... the LBS is the safety net and the affair is the tightrope the WS walks along...
Once you STOP being there... particularly by shutting your WS OUT of your life and they have no idea what you're doing or where you are going, the WS has to go back and check the safety net...
The begging, the pleading, the pursuit, the constant contact, even curses and blaming ALL REINFORCES to the WS that the net is there in tact.
Even threatening divorce won't stop them... when they SEE that the net is being taken away, or they are shut out of the LBS' life and don't KNOW anymore (effectively blinding the WS) they are forced to backpeddal...
This is why its so very important to expose the affair and then dissappear... this takes away the safety net AND shakes up that tightrope like crazy...
With a tightrope starting to unravel and the WS can't see a safety net in site panic will set in...
