One other question: if one of my W's stereotypical complaints about me was that I wasn't demonstrative enough of my affection for her (e.g. arranging dates and buying her flowers/cards) how can I 180 that behaviour if I'm not supposed to do that stuff for her now?
It is pursuit especially if she is in an active affair.
Like an alcoholic saying I quit vodka and changed to beer. A change but not the right one.
Yep -- BINGO. All of that goes out the window once they are having an affair, and you KNOW they are having an affair, and they KNOW THAT YOU KNOW that they're having an affair. Dynamic totally changes, and to continue to pursue her sexually is only going to further emasculate you in her eyes.