I did it. I contacted her, against the better advice from many, I know, and with great anxiety. I sent her a short text yesterday morning demanding that she stop interfering with my marriage and find someone else, preferably an unmarried man.
My reasoning for this communication was partly based on forcing an issue - though my H said he hadn't been in contact with her since he last agreed to cut it off (about 2 weeks ago) I felt that the text might push her to complain about it/me and I wanted to see his reaction to be able to gauge the truth of what he was telling me about contact. Convoluted reasoning, maybe, but mine.
Yesterday afternoon she called me (first time ever in 6 years). I was driving from Michigan to NY with my daughter and almost didn't take the call, but decided after the second ring to answer, steeling myself for what would come next.
She very politely said she had received a text from my number that morning and I said 'yes'. She said the message said leave my marriage alone and I said 'yes'. She said "Is this a joke?" and asked me my name. I told her and she said "are you related to GSdad, and I said yes, I'm his wife. And she lost it. She was I think truly surprised and shocked and angry, etc. I know I may be acting gullible, again, but I somehow felt her response was genuine.
We talked for about 90 minutes, comparing notes and sharing what we knew and I think I have finally heard the whole/most of the whole story. And others here were so right, there was so much more to know. But I feel mostly relieved. I'm still get some fleeting doubts about her and everything she said, but I think for the most part it's all true and accurate.
I now have to figure out what my next step is in confronting (again, for the way too many times) my H. But now, I'm ready to push him out. He is really a manipulative liar and he has tried to maintain 2 lives, one with her and one with me.
I'm at my daughter's home, trying to help her get ready for her first baby while her husband is deployed in Afghanistan, and I won't leave to go back and take care of this for a few more days. Which is probably good because it gives me time to plot how I will lower the boom. But I am ready. It has taken me almost 6 years of on and off mixed motivation and belief, but I am ready. I have the confirmation, from her, of what he has tried to (and has rather successfully succeeded in) keeping from me.
Any advice on this kind of determined confrontation would be appreciated.
Please wish me luck and courage.