I think your therapist is really off the mark (and alarmingly ageist, to boot).
NOT knowing the truth poses a greater risk to the other BS than being told, IMO.
Older or not, the man deserves to have the knowledge required to make informed decisions about his life.
In your shoes, I'd be seeking another IC. The first "Examine your motives" I heard would be enough to tell me that the therapist's motives were off the mark---and wondering whether s/he is a WS.
It is difficult--emotionally and often logistically--to tell the other BS. But there is NOTHING worse than being in the dark about your partner's infidelity, other than being in the dark with suspicions and being gaslighted.
Suggesting that the man be allowed to die without being told? Well, that makes a whole bunch of assumptions, doesn't it? It first assumes that he's too feeble-minded to sense changes in his marriage. And it then assumes he's too physically feeble to survive the news.
Nonsense.
There is a very, very good chance that the other BS does have suspicions. Most of us can tell, on some level, when our spouses are diverting attention/love/care from the marriage elsewhere. Most of us DO find out, eventually. And as one who was kept in the dark long-term, I can tell you that it is SOUL-crushing to learn that others have lied to you, over years. Talk about humiliation.
I do agree with one thing your therapist says: it's wise to back off trying to direct your husband's actions. Not because they don't need direction, but because you just can't do it. The only person whose thoughts, feelings, and actions you can control are your own. While many of us wish we could direct our spouses in the aftermath of infidelity, any attempt to do so is an utter waste of time and effort; it has to come from them.
So focus on YOUR thoughts, feelings and actions.
If you believe that telling the other BS is the right thing to do, then do it. You do not require the permission or approval of your IC. You won't get it from your husband.
But the man has the right to know. He has the right to make informed decisions about his life (and if your IC is right about his proximity to death, about his estate and his healthcare proxies, as well---because if I had one foot in the grave like your IC assumes this poor man does, I sure as hell wouldn't want the woman who was lying to me making end-of-life decisions if I was not able, and I would want to change my will).
But really, chances are he's just a nice guy with health as good as the next guy--- who deserves the truth and would be wise to get tested for STDs.
(I sent a registered letter to the OBS's place of business so that it could not be intercepted. You might also talk to him on the phone, or ask to meet him for a cup of coffee. There are many ways to get past interception by the WS.)
[This message edited by solus sto at 6:46 PM, June 29th (Saturday)]