I believe all intimate cross gender friendships must be "open" friendships. I don't believe there should be any "closed" or private cross gender friendship--especially when marriage is involved. Cross gender friendships need to be open from the beginning and stay open. As a matter of wisdom, that's a big commitment to maintain and hold in cross gender friendships between a man and a woman who are married but not to each other, or a spouse and an opposite sex single friend. One of my closest friends is a single woman. There's no way we'd be as close as we are, if I had not practiced, if we had not practiced an open cross gender friendship. There's a paradox. I enjoy this deep intimacy with a single woman friend precisely because it is an intimacy open to my wife and my mentor friend. I would not though, seek any cross gender friendship with a married woman if she could not also keep it open with her spouse.
Online cross gender connections and friendships must be accessible to our spouses.
You should always be open and honest about your cross gender internet correspondence with your spouse.
I strongly recommend that all email accounts should be open for your spouse's viewing. You should never set up a separate email account that is not accessible to your spouse when we are talking about cross gender friendships.
Emotional intimacy is possible in cross gender friendships as long as you have emotional primacy with your spouse and are open with your spouse about the emotional intimacy with your cross gender friend. I really do think, and this is from a male perspective that men need trusted male friends whom they can talk about the cross gender emotional intimacy, too. It works even better if your wife trusts the male friend. In other words, I never advocate an exclusive, private cross gender friendship.
All my female friends know whatever they share with me is open for me to share with Sheila.
Keeping the friendship and emotional intimacy "accessible" to your spouse cultivates ongoing, deepening trust.
Accessible doesn't necessarily mean that your spouse must hear every conversation, see every email, or be with you every time you meet. Those are issues of trust for you to work out with your spouse. Accessible means you don't practice a secret relationship with your cross gender friend. Sheila knows a couple of my cross gender friends; she knows the nature of our emotional and spiritual intimacy between us, and therefore deep trust is present.
Open means too--an open heart, open to your spouses' input and heart at all times concerning the emotional intimacy you share with your cross gender friends.