Is it obligatory to safeguard the trust of one who curses the the Messenger of Allah, peace and blessings be upon him, Islam, and Muslim women?

Whoever insults the Prophet, peace be upon him, or Islam, apostatizes and becomes a belligerent, and it is permissible for the ruler to punish him with death or otherwise. However, it is not permissible for a Muslim to betray a trust concerning an email password, for the Prophet, peace be upon him, said: "Render back the trusts to those who entrusted you, and do not betray him who betrays you." And if Muslims fear betrayal from disbelievers, they do not act treacherously towards them but rather inform them of the termination of the covenant, as Allah Almighty said: "And if you fear treachery from a people, throw [the treaty] back to them on equal terms. Indeed, Allah does not like traitors." Therefore, it is not permissible for you to disclose this disbeliever's email password, and you must sever the relationship of affection and friendship with him.