I mean the compartmentalizing? yes, an A is a selfish and cruel act. But, how does a WS just wave it away and act like all is normal?
How does a WS still come home and be part of a "normal" sexual married relationship.
Yeah, there are open/loose marriages and relationships out there; but by and large we are talking about lies.
Why bother keeping a marriage going. Having your cake and eating it too?
I've been through this twice. I'm still shaking my head wondering why? Why, stay in a marriage as a WS.
A real ONS is one thing, but most of the people here are suffering from more than that.
Even now I ask my WW why she wants to be in this marriage and she says she loves me. That she want this marriage.

I can chalk it up to some selfishness. But, there has to be more. Disregard for the BS's feelings? Or just disregard for the BS?

It's how the justification is allowed to happen.

DD,
Yes to selfishness, yes to disregarding BS. The only thing I can come up with is that humans are not perfect and we do stupid things. I didn't go through it twice like you. Honestly a second time for me would have me leaving the M - there's just no way I will accept it a second time and I'll tell you why: After the first time there were things I needed to change with me and how I treated the M. I've done my part to keep our M and R successful. If my FWH decided to have another A I would walk with peace of mind knowing he didn't deserve me anymore. DD, also I've read enough here to know that people go through different stages in their life. Some are more vulnerable than others and they need more help. You ask Why does your WS want to stay married to you? Well - she has to love you if she wants to stay so that is a good thing no? I do believe WS sometimes have affairs on purpose to get H or W attention to focus on their M. Do you think this could be case with your WW? I'm sorry for your pain.

But this *IS* normal for a serial cheater. They are people who can inflict great amounts of cruelty and thoughtlessness on others and then say "but I do love you!" They are very dangerous people. The serial cheaters I have known did not recognize any usual standard of right and wrong. For example, my fathers moral standard was what "makes me happy," not what is right and what is wrong. I suppose we should be grateful he wasn't a serial killer.

When your WW says she loves you, what she means is she likes having you around. You make her feel good, you meet some ENs, she gets something positive from being with you.

Her "love" is a self centered, taking love.
It's not a love that is built on acting in a loving manner and protecting her spouse and her marriage.

"I love you!" from her mouth means you are (one of) her favorite pairs of shoes. She would really REALLY miss you if you were gone.. to her that's proof that she loves you.