First of all, millions of hugs to you. I know --many, many of us know-- the pain that occurs when what we believe to be the extent of an already heart-rending infidelity is broadened to include things we'd so wanted to convince ourselves did not happen.
The impulse to believe the lies is so, so strong. Often, believing the best of our spouses is the only thing keeping us going.
But there comes a time when protecting our own hearts gets in the way of what is best for us and--in this case--our children.
Your husband did not just "kiss and cuddle" over wine in a hotel room in Europe. I'm sorry. I know you want to believe that and, perhaps, needed to believe it as the horror of infidelity sunk in. Sometimes, we have to let information in incrementally.
But now it's time to open your eyes a little wider, and take in the truth. You may not have the WHOLE truth yet--but I think that, if you're honest with yourself, you will admit that your gut knows that, in Europe, at least, the happy nights drinking wine involved sex.
I'm assuming whilst they were drinking and flirting on this Europe trip they were in loco parentis for a group of school kids
This, alone, warrants a report to the Powers That Be at your kids' school. It demonstrates a lack of care for the well-being of the students in their charge.
Given the brazen lack of remorse demonstrated by both your husband and OW, I would guess the affair is still ongoing.
Your husband may never admit the extent of his affair. You may never amass concrete evidence. But here's the thing: you don't need either of those things. Because you know.
Just the OW's and your WH's words alone, at this point, are evidence of their entitlement, delusion, and dishonesty.
They chose to have an affair, and continue to remorselessly lie and gaslight. They tell you you're over-reacting.
The OW's cold selfishness, as evidenced by what she's said to you and the tone in which she has done so, makes me literally cringe; as a BS it hurt to read that, in all its unrepentant Me-Me-Me gaslighting glory. It's ALL about her---and a teacher who has that attitude toward the MOTHER of these children should not be permitted anywhere near them. That your husband is on the same page as OW is incredibly worrisome. Incredibly.
You are NOT over-reacting. That either your husband or OW would suggest that shows the level of delusion they are experiencing. (File it under, "If they don't know, it won't hurt them." And then ask yourself, "Am I hurt?" The answer is yes. Now imagine your children with that hurt---and you have your answer about over-reaction.)
In your shoes, I would let the school's headmaster/principal, superintendant, and board of directors know of the affair-- in writing (to all) and in person (headmaster/principal).
Teachers are supposed to be of high moral character. They are supposed to model appropriate behavior for kids. Realistically, though, we all know they are human; a blind eye might be turned if the infidelity impacted no one in the current environment. OW might be told to be more discreet so that students' parents did not have occasion to see her behavior. She might be told to keep it under wraps. But she likely would not be fired.
But when the children DIRECTLY affected by an affair are expected to be in close proximity to the woman who wrought havoc in their lives, then "just human" doesn't cut it. "Be discreet and make sure there aren't any parents who might complain about your conduct around to see your inappropriate behavior" is not enough. Children being hurt is NOT AN OPTION.
I would ask for her dismissal.
If the school is not willing to terminate her employment, you can be damn sure I would pull my kids from the school. The teacher is NOT "a signature on a report card twice a year." (That an educator would distill his own role down to that is further evidence of the level of dishonesty and delusion still at play.) She is a looming all-day-every-day presence in your kids' lives--one who has NO compunction about harming them. (The lovebirds can lie to themselves about this if they want, but neither of them have the kids' best interest at heart.
The odds of emotional fallout hitting your kids is astronomical---particularly when the affair ends.
Now? Having her around them definitely sucks. But imagine how your kids might be targeted/scapegoated/whatever by this woman who feels ENTITLED to their father--if they really do end their affair, and your WH owns up to the whole truth, and goes NC with her. I think the potential for harm to the kids is very high, and the prospect is positively horrifying.
[This message edited by solus sto at 11:02 AM, June 4th (Tuesday)]