Being civil with her is a real good idea. Cultivating a friendship with her is not.

How much you have to do with her depends, somewhat, on if you and your ex have kids together. I don't know whether or not you do. Even if you did, "civil" is about as far as I would go. "Civil" preserves your dignity and actually conserves your own mental energy and minimizes your stress - now and in years to come. "Friendship" is inappropriate and opens you up to ongoing drama, now and down the line, that in no way enhances the quality of your life. I haven't yet read this whole thread, so I'm sorry if I've missed some relevant information. But my advice still stands regardless. Would I trust a woman who got involved (or stayed involved) with a man, after finding out he was married to me? H€II no! Not saying she's a totally bad person - I don't know her. But here's what I do know: she believes down in the deepest part of her soul that you did not deserve the man you were married to, and she did. That pretty much would eliminate her as a potential friend to me, if I was you. Your ex-husband also believes that. Those two, for the rest of their time together, will be looking for evidence to support that belief. You don't need that. Any sweet conversations she might have with you are very different from the way your ex and her discuss you went they are alone together. So right there is an element of phoniness built in to any relationship you would have with her.

If you are lonely and in need of more friendship in your life, then do something constructive about that . . . but not this. It would make you kind of pathetic.

It can be tempting, after losing a marriage, to want to take advantage of opportunities to know what's going on in your ex's life. It's also very unhealthy. It's a way of refusing to "let go." Don't do that to yourself. Stop clinging to what is not yours anymore. Move on and move forward.

Be careful, also, of how you define "civil." Don't overdo that. "Civil" means that you see this woman when circumstances force you to. You don't listen to her problems, and you don't tell her yours. You comment on the weather and keep the conversation quite superficial. That's what "small talk" was invented for - a way of being pleasant without opening up to much.

Good luck. Save your friendship for persons who can bring something good into your life. In your heart this lady will always be associated with great pain. Don't embrace that.