I don't see why you'd have to hide an emotionally intimate friendship in the first place, personally.
Me neither, which is why, by hiding his "friendship" with another woman, my WH was engaging in an EA. Now, he had EAs with other women too ... women that I knew about, but did not understand what an EA was. I still think he had a PA with at least one of them, but he denies it. And I've said that if he had not had the secret EA or any part of any PA, we would probably still be chugging along in our happy M, and he'd be getting plenty of ego kibble from all those women friends, and I'd still be clueless about what an EA really is.
But he didn't do that, so his PA put me in a place to learn about EAs, and the problems they present. Not bc of the friendships, but more bc of those relationships become an escape for him to avoid having to learn to love himself. Why dig into that whole can of worms if the women-fed ego kibble is endless? Except that like any addiction, that kind of soothing is not healthy. And to me, that's the difference between a platonic friendship with an OS and and EA.
I think Shirley Glass gets into the walls/windows analogy, or it may be Gottman. Spouses are to have a window between them to allow for open and free communication - that includes a deep level of non sexual intimacy. Intimacy is between the spouses, and there are walls around that intimacy, because it is not to be shared with others outside the M. A truly platonic friendship with an OS person does not interfere with that dynamic bc it does not threaten or change where the walls of intimacy (sexual or not) are between the spouses or their outside friends - the spouse would not share, say, sexual details of their M with their OS "friend" because that is something that needs to be discussed with the other spouse - not a third party.
But in an EA, the spouse engaging switches the wall & window, such that there is a window into the AP, with the wall replacing the window that used to be / SHOULD be with the BS. Now, I do think that what levels of intimacy are Ok to share and what crosses a boundary probably varies from person to person. Personally, I did not feel threatened or offended by my WH's "work wives". But in retrospect I should have, bc one became a (albeit brief) PA. And even if his LTA EA had never turned PA, I would have felt very offended and hurt by the SECRECY of his relationship with his POSOW - bc it was a relationship that unquestionably created a wall between he and I (bc it was a secret - and even before the PA, included lying and deception), and a window between he and POSOW (bc of the secrecy and bc their conversation topics absolutely exceeded the boundaries of "friendship" intimacy [eg reminescing about how great their sex was, her sharing all the personal details of her M and her sex life. My WH denies sharing our marriage details with her, but who knows if that is or isn't the truth]). Some use the "down & dirty" description as doing or saying anything you would not do in front of your spouse - and his LTA EA absolutely fit the bill. I may be bungling this, and someone can correct me, but that's how I understand it.
I do think that Glass' book is titled "not just friends" bc her research shows that these friendships can be on the slippery slope to an EA or PA (or - in all too many cases, both).
I do not subscribe to the concept that it's not possible to have friends of the opposite sex. I have many (in fact, I've probably had more male friends than women over my lifetime - and I've never had an pA or an EA, in that I can't think of any of those friendships that were either too emotionally intimate or that created a wall between my husband and I) HOWEVER, I do believe that some folks (ie WS) just can't do it - same as alcoholics. So, IMO after an A, OS "friends" should some completely off the table. Because my WH has proven that he is incapable of holding any boundaries with other women, I am very leery of any OS friendships or even being alone with women. Just like an alcoholic should probably not work as a bartender bc it's too easy to fall back into bad thinking. And we - unfortunately - all know how easy it is for someone with wayward thinking to start lying to themselves (and we also know that, like alcoholism, WS are statistically relevant for relapse)
As for bisexuals - sounds like it would be really tough to navigate and find boundaries. As Brene Brown says, we are "wired for connection", so even WS need to have connected relationships/friendships. I assume that those who have dealt with same sex APs would have some light to shed on that front.
[This message edited by gmc94 at 4:27 PM, December 20th, 2019 (Friday)]