Once again, an interesting topic for thought, Uncertainone!
I totally agree with this in the simple sense:
The "if you hadn't don't xyz then I wouldn't have done abc".
But I recognize it gets a whole lot more complicated sometimes.
We all came to this site because of infidelity whether we are a BS or WS, and for that reason, I understand that a lot of topics revolve around the rights and wrongs and the choices we make as they relate to infidelity. But in the larger scheme of things, we do rights and wrong and make choices due to a lot of things that have nothing to do with infidelity (but might be just as bad in the eyes of some).
I actually agree that many BS will post and vent on the forums, blaming everything that is wrong in their lives, and their own continuing questionable choices, on the fact they were cheated on. Once in awhile they get called out on it, but I think most often, they get support and some form of agreement that everything wrong is all the WS's fault.
I think in a lot of marriages, there are big problems that can lead to an increased chance of cheating even though that is in no way a justification for anybody's choice to do that.
The one biggie that comes to mind is when one has a low or non-existent sex drive and the other has a high drive and the one with the low drive always rejects and just doesn't seem to care about the needs of the other. I also recognize the one who ends up cheating is sometimes just looking for closeness, intimacy and warmth, as much as they are looking for sex. And if this is missing in the M, sometimes it really is mostly the fault of one person or the other (not necessarily both, but also could be both...that is my opinion).
In my observation, even when a new BS comes on the forum to admit this huge problem was a precipitator to their spouse having an A, many BS will come on and say essentially "no, that is not the reason he/she did it. It is because he/she is BROKEN (or whatever). And they will offer up evidence of their own case, where they had sex every day for 20 years, whenever he wanted it, and he still cheated. (as if that is any evidence at all to why somebody else cheated after years of trying to work things out with the lack of sex or intimacy).
And in spite of what I have said here, I feel that both of my H's were almost 100% at fault for not only their choice to cheat, but also for anything that was wrong in our M.
I would be one of those who did everything possible to make my first H happy, to be what he wanted in a woman, and never or rarely reject. Yet he went to prostitutes and cheated on me all throughout our M. No, I won't be taking any blame for that, none at all. He has never once implied it was my fault he cheated, so I can't say he blameshifted that. Everybody has their own thing though. He did not blame me but he downplayed it like it was not that big of a deal...just another sin like overeating, or something. So I should not be so mad. He also told people it was both our faults we got divorced. (Yeah, the only way it was my fault was because I kicked him out after the last d-day and filed...I could have just continued to put up with it, I guess).
In my current M, I did acknowledge some things about the "environment" in our M that I could improve on my part and I have worked on that, quite successfully, I believe. We had been fighting over our business and things my H was doing behind my back financially, at the time the A started. Well, how could that be my fault? It wasn't and I'm not sure there was a right way to handle it but I know during that time I was calling him a stupid idiot and putting him down a lot, and telling him he was "bringing me down."
He claims he started to feel I would actually be better off without him. And then the OW came on the scene, flattering him every day (having no clue about his unwise business decisions and the late payments he had going on and all that, of course) probably telling him that he was a brilliant business man and essentially on the same level as God. None of this gives my H the reason to cheat, but it is something that I felt needed to be looked at in our story, and is a tad more understandable to me than what my XH did.
But a biggie for me is that my current H never blamed this on me. He never once brought up me calling him names, except for he did say that he did come to believe he was bringing me down. He has consistently told me for seven years now, that none of it was my fault, and he is extremely sorry. Even though I think I have actually improved myself, he has made it clear that I really did not need to as some "condition" for him not repeating the behavior. He makes it clear he loves me as I am, and it was not my fault he got involved with OW.