Answered by Shaykh Yusuf Weltch
Can you please tell me the ruling on having friends and companions of the opposite sex? Even if 1st or 2nd cousin, would it be permissible for them to phone and message one another? Is the spouse entitled to be upset?
In the Name of Allah, the Most Merciful and Compassionate
In general, relationships and interactions with the opposite gender should be limited to times of necessity. When a need arises, in which one must interact with the opposite gender, it should be done in a formal manner with the proper etiquettes.
Etiquettes of Interacting with the Opposite Gender
One should refrain from any private messaging or phone calls. If there is a necessity, email is a more formal alternative. One should not meet with the other in a private place or to be alone with the person. Also, one should refrain from any seductive speech or excessive joking. Rather the speech should be purposeful and to the point.
The Rights of the Spouse
It is within the rights of the spouse to not want their partner to be interacting unnecessarily with the opposite gender.
Hope this helps
[Shaykh] Yusuf Weltch
Checked and Approved by Shaykh Faraz Rabbani