First of all: there is a substantive difference between memories/what's going on inside your head AND fresh action by a third party. Trying to conflate them so you feel better about concealing the OMs phone call seems like very poor logic, to me.
People may not be commenting on your SSM because it's just too hard; although there may be repeated patterns, every SSM is usually a tangled-up mess of a lot of things (things the participants may or may not be aware of) and it's hard to give an outside opinion.
However. You might want to spend some time considering this: Is there a relationship between your extreme disinclination to needlessly "hurt" (and yes, defend this as you may, this is still mind-reading) your husband with fresh news of OM and a historical disinclination to "hurt" your husband by being very open, up-front, and persistent about your dissatisfaction with sex in your marriage?
It's hard to think of a more vulnerable place to hit someone than in their sexual efficacy. Telling your husband he wasn't satisfying you sexually probably did hurt him. As long as you were being honest about your needs and not saying it to be vindictive ... so what? People hurt each other, even when they love each other, it's inevitable and even sometimes necessary. Where is it written that his hurt automatically trumps your hurt?
I say this because *now* you sound like a person who is almost pathologically afraid of being "the person who hurts someone". The problem with this -- beyond the fact that it devalues *your* humanity -- is that as long as you feel that way, your tendency will probably be to conceal anything hurtful, including your true needs and desires in the relationship. That way lies the risk of ending up right where you started here, in another fun, vow-free lightweight affair that (paradoxically) you can enjoy *because* you don't care all that much whether you hurt the OM or not.
I may be completely off-base, but it's something to think about.
"Show me a completely smooth operation and I'll show you someone who's covering mistakes. Real boats rock." -- Frank Herbert
