About all the comments above. The issue with that line of thinking is threefold:
-extreme greviances are the norm for this type of stories, but that does not make it the rule
-if you actually think about the morals of the era, cheating is quite common after consumption or the marriage fell through. It's clear that while the her from her previous life wasn't innocent, the only vice she initiated was her spending habits. For the cheating, she was already ostracized, was approached, courted, seduced and led by the nose. She was made to believe in a love that didn't exist.
-she never attributed her bad end to external factors, she attributed it to her way of life, past mistakes, bad decision-making. If anything, she did not even blame the second prince who was behind the plot or the man who manipulated her. If she isn't worthy of a restart, no one is. Her heart is more pure than any other protagonist.