In my 10 years or so on this forum (first as Chocolateeyes, then Puppy Dog Tails, and now Starsky) I've seen many, many people -- usually MLC'ers, frankly -- confuse "standing" with "being a doormat."
Standing means to stand for your marriage, WHILE not standing for the adultery and WHILE establishing firm boundaries to protect yourself. Often, it even involves REMOVING yourself from the situation. The stander won't initiate divorce (something I disagree with, but I can respect it) because they are "standing" for their marriage, but they absolutely are NOT communicating to the adulterer "I will be here for you no matter what," and they are NOT saying some of the blccccch I see on here sometimes about "helping them along their journey" and such.
Usually, such behaviors are rooted more in FEAR and CO-DEPENDENCY, all the while being wrapped up in a cloak of courage and "standing for my marriage" and "doing it for the children." I would argue, in fact, that these people are teaching their children exactly the wrong way to deal with emotional abuse.
That may sound harsh, but that's been my observation. The successful MLCers that I have seen learn to stand WHILE establishing (and learning to enforce) strong boundaries.