To be perfectly, bluntly clear- There isn't actually any suffering (and in some cases, still almost none) until the secret gets out.
By that definition (which to me is entirely obvious, but clearly not to others), OUTING all of these people is what will cause tremendous suffering.
I don't agree with these blanket "everyone who does this is bad" statements. (I think there's a lot of people who have been cheated on out there and their latent scorn always comes out in these things. Rationality goes out the window when personal feelings are involved.) It's awfully judgmental and sandblasts out all the fine details. What of the man who wants to stay married to his invalid wife but still needs to "get off" at times, and neither wants to break her heart nor can he longer function rationally without? What of the good husband and father who is hiding his bi-ness and therefore takes a man now and then on the side? (What of the woman in the same position?) What of the member of the church demanding absolute celibacy who has invested his life into it but realizes he simply can't function without sexual human contact now and then?
Do you seriously expect the amount of upheaval that would result from "outing everyone" to be LESS pain overall than the current situation?