Been with DP 10 years and have a 2 year old together.
I had a feeling something wasn't right and rightly or wrongly I checked his phone.
He's been messaging a girl I kind of know and it's clear he's slept with her at some point years ago. He mentions how they went back to a club after which shut before we were together which makes me assume it was before we met. He's been saying how it was great and the best he's ever had, going into intimate detail. She's married now and just replies by saying yes to be young again, or just laughs it off. So it's clearly him that's trying to bring it up more than her.
I've not mentioned it to him yet. What would you do?