May - for what its worth, we all went on a RV trip together down the Oregon coast. My H was in contact with her, I knew that, but I didn't say a word. Yeah, that part sucked, but I focused on the trip, getting out, being with the kids and really enjoyed myself.
I mostly kept my mouth shut around him. If he wanted to converse, then we did. When he seemed cranky, I just gave him lots of space. He never seemed happy and would never say he enjoyed himself. But later, much later, he told me how much fun he did have - and how he enjoyed being with the family- and how all he was doing was heavy on his mind. They KNOW they are doing terrible things. But it makes them feel better when WE are acting "badly" because it just confirms that we are bad spouses and its really our fault.
I know your H is way different than mine, so shut him out when he gets chatty - focus on bonding with the girls. Let him see what he would be losing if he did pursue the ow. Don't get baited. Smile, be friendly or at least cordial, make the coffee (if your making your own) and swallow your pride - be agreeable. You can cry in your bunk at night. He KNOWS your hurting, he is not blind. Figure out what is your goal? Do you want to be together? if so, work towards that don't get tripped up in all these R talks, at least put that away on the trip so you can enjoy it and make some great memories with the kids.
M:50 H:49 D:16 S:13 M:23 T:25 BD: Feb 25th 2020 EA/PA: Dec 2019 - June 11, 2020 Behind every broken woman is a broken man...