Book 56, Hadith 215
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Narrated Ibn `Abbas: That he heard the Prophet (ﷺ) saying, "It is not permissible for a man to be alone with a woman, and no lady should travel except with a Muhram (i.e. her husband or a person whom she cannot marry in any case for ever; e.g. her father, brother, etc.)." Then a man got up and said, "O Allah's Messenger (ﷺ)! I have enlisted in the army for such-and-such Ghazwa and my wife is proceeding for Hajj." Allah's Messenger (ﷺ) said, "Go, and perform the Hajj with your wife."
How the Prophet ﷺ modelled this behaviour here
Fierce Loyalty
Protecting the marriage by maintaining complete transparency with devices and refusing to spend time alone with men outside her immediate family.