My read: she gave signore a second chance, but where's the second chance for SP after x years of marriage and two kids?
I'm guessing that's where the rancor is coming from.
Regardless of where the rancor is, the fact remains that she did give her partner in adultry a second chance...and her husband of 18 years and the father of her children gets no second chance. That's painful, and SP's angst is quite understandable to me.
"Always go straight forward, and if you meet the devil, cut him in two and go between the pieces." - William Sturgis, clipper ship captain, 1830's.