I personally would rather know than not know... by not knowing I'd feel like a fool and it wouldn't provide me with an opportunity to try and save my marriage. For example, initially before I knew about OW, I took my husband's criticisms personal, got mad and reacted. If I had known about the affair I would have realized that his actions and anger were due to other things and I would have reacted differently.
When I spoke with OW's husband. I presented information unemotionally. I told him I strongly suspected his wife was having an affair with my husband (even though I was certain) and then I described what incidents led me to believe this (i.e. phone records which I mailed a copy of to him, timing of certain events, that my husband mentioned something about moving out where they lived, etc...). I was always careful to present it as a "suspicion" and explained that I felt he had a right to know if there might be a threat to his marriage. This way he could try and figure out what might be wrong and fix it. I then wished him luck. I didn't give him my phone number and didn't actually speak with him again.
BTW, information you've heard about OM's W and their marriage from your W may be complete fiction. Also, I am probably the least "frightening" person on this planet, but I think I could have turned into an enraged bear with OW. The anger over someone hurting my marriage, my family and particularly my kids was HUGE.
There is no arriving, ever. It is all a continual becoming.
