In desperate need of advice, separation looming!

[AnotherNightmare]

First thing I would say is stay calm. It really does not change anything as to how you need to handle yourself.

It sounds like there is an EA, possibly a PA going on. First of all, it confirms that you should not move out, under no circumstances. That would just open the door for her to invite him in. So be tough on that. No moving out.

The second thing you need to think about is whether you want to confront her, or expose the EA/PA, or do nothing. Take your time on that decision (at least sleep on it once or twice), and play it by what you feel is best for you, not how you could possibly do less damage to your M. She determined to end your M anyway, so nothing you are going to do will change that.

If you do confront, be very matter-of-fact about it. Something like "I know everything about what is going on between you and 'Matt'. It is extremely disrespectful to me and our family." That is it. Do not tell her your source. Then you need to decide if you want to expose to friends and family. I would do that if you think you get their support saving your M.

In any case, you need to continue to work on yourself, trying to be the better option for her. That is all you can control right now. You cannot control what she is doing, whether or not she is going to the concert with OM. So do not even think about it. You feel powerless and angry, but where you need to go is a PMA.

This is not over. So hang in there.