I see 2 issues in this thread.
One - informing OBS - is a small one, though it takes courage to resolve it. Inform her. Let her know her H has endangered and maybe destroyed their M and damaged her physical, emotional, and financial well-being.
The 2nd - should you end your M? - is much more complex.
You say you love her. Does that mean you'd like to R? It's important to know what you want, even if you don't see how you can get it.
Have you discussed her getting a new job? That's not a permanent solution, but it makes NC possible, and there's no R without NC. Is she willing to get a new job? If not, R is probably not likely.
You say she won't get counseling. If you're in the SF Bay area, I have a hard time imagining a company that will object to an employee's getting counseling, so her 'reason' is very questionable, IMO.
She didn't cheat because your M failed; she failed. Something in her enabled her to cheat. The low self-esteem that you mention could be it. Perhaps she allowed external validation (nice words and touches) from om to boost her self-esteem.
In any case, for R to succeed, she needs to change from betrayer to good partner, and that will almost definitely require counseling, which is readily available in the SF area.
Do you have requirements for R. Usual ones are: no more lies/answers all questions without TT; NC; IC for WS; transparency and access to all media; IC for BS, if he wants it; MC, when one partner wants it.
Those are all observable. If you monitor performance you can get an idea of where you are in R. If, for example, she breaks NC, it's a clear violation of your agreement, and consequences follow. If your gut says she's holding back the truth, she's probably violating your agreement; consequences follow. Etc., etc., etc..
*****
I don't understand the focus on exposing the A. Yeah, it kills As, but that leaves the BS open to being the default.
R needs both partners to want it enough to do serious, difficult work. If the WS comes back after the A is exposed, it's too likely that s/he just wants a comfortable port in a storm ... until the next flashy object shows up.
Exposure seems more beneficial to the BS if the BS chooses D - but even that is iffy, because exposure can do financial damage, especially in the case of an on-the-job A.
JMO, of course. I could easily be missing something....
*****
I strongly recommend that you make your goal 'survive and thrive' rather than D or R. You can survive and thrive with or without your WS.
R requires 2 participants, and the BS cannot control the WS. So look to healing yourself first. Figure out what you really want. If it's R, then pay attention to whether or not the WS is a good candidate for R.
[This message edited by sisoon at 1:21 PM, April 6th (Monday)]