Using her power to change forms, Sati took the form of Sita and appeared before Rama. Lord Rama immediately recognized the true identity of the Goddess and asked, "Devi, why are you alone, where's Shiva?" By this, Sati realized the truth about Lord Ram. But, Sita was like a mother to Lord Shiva and since Sati took the form of Sita her status had changed. From that time, Shiva detached himself from her as a wife. Sati was sad with the change of attitude of Lord Shiva but she stayed on at Mount Kailash, the abode of Lord Shiva.
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