Thoughts?

As someone who has been going through this for the last almost year... My advice is don't tell them. We told our 15 year old son that we were splitting do to his father's infidelity and I honestly regret it. He hates his dad now... Doesn't want anything to do with him, and now he has self doubt and is worried that because his dad did those things he's now a bad person. I have him in therapy.... But if I could go back I wouldn't have told him that part until he was an adult and better able to handle it.

Children don't understand adult relationships, so it's best to keep them out of it. My ex partners father cheated on his mother, and he still doesn't know that's the reason they split. She confided in me and made me promise never to tell him. Ultimately, I think knowing would have harmed his relationship with his father, and that's no fair on a child or the adult they become.

My recommendation. Under no circumstances explain what’s going on with your kids unless you and your wife agree to what will be said. Older teenagers are still kids, and have a perception of each of you. In my opinion it is wrong to get them involved in Grown up Sh&T ( they are kids). At the end of the day, they will figure out what happened and more importantly will observe how you handle the situation.

well that's great advice until you lived it, my dad as I've posted for years left my mother ( she cheated) i hated my dad for many years and he held that secret so i wouldn't find out. I ignored him, skipped visits, hated his wife, didn't like my half siblings, two years ago a someone told me the truth. I begged my father for forgiveness, he responded and said "you're my son you dont need to ask i love you and always will" I've completed cut my mother out my life, she always made it out to be my dad and he took it all because he thought he was protecting me, ive finally broken the shackles from my mother and I'd never speak to her again, I lost twenty years with my father because of those secrets.

You tell your STBXW you can prove she cheated. If she turns the kids against you during the divorce, then you'll offer them the proof. It isn't their business. You and your STBXW need to continue parenting your children. It's more important than you feeling vindicated or proving that the divorce is necessary.