“Kay may be absolutely furious that she can't go to Tahoe social functions anymore without people laughing at her”

No kidding! Pete, Are you pulling my leg?!

Michael's public image was not tarnished
In fact he was exonerated, without a blemish, no proof linking him to any criminal conspiracy
Michael's lawyer, Tom was even demanding an apology from the senate committee!

Kay's that look was indeed looking daggers at Michael Well their bedroom had just been machine gun sprayed......

Michael and Kay, when they were dancing at Anthony's party, seemed quite loving in spite of Kay's legitimacy gripe and Michael's reassurance that he was trying
They spoke lovingly about the baby feeling like a boy
Kay was already in bed. Michael sees the drawing Anthony left for him on his pillow, reaches over and strokes Kay's cheek

Whilst Kay didn't even look up from her sewing machine when Michael returned from Havana [was Kay aware Michael was actually home?] Michael also didn't even bother to enter the room to comfort his wife who just had a miscarriage? That was troubling indeed

And Kay did attend the senate hearing every time like a dutiful wife, sitting by Michael's side and the next scene Kay is leaving Michael?

Kay not bringing another one of Michael's sons into this world, changes little or nothing regarding "this must all end" as they already had a son

“Kay was finished with Michael's way of life” but still leaves her children behind in that way of life