Sweet Psycho's Revenge SPR

She has a secret but she was already contented with her life. She has a loving husband who gave her everything. She was living in bliss with their cats and dogs. Everything was perfect even without a child. Everything was doing well and smoothly until one day, she wakes up covered in blood. Lying beside her was the lifeless body of her husband.
Unjustly accused of murder, she plotted for revenge. She has nothing to lose when everything was taken away from her.
She had one hidden card, and she will use it as she slither her way to the camp of the enemy.