I brought it up because it happens, and it's a real reason to not have affairs. When you lie to people about being monogamous, and sleep with someone else, you endanger them.

I know people who found out about affairs from the STD. It's an ugly way to catch a cheater. It's a really good reason not to cheat. If you respect your spouse, you don't make them vulnerable that way. Period. No matter how bad a marriage is.

Dad was disrespectful to his ex-wife and children. He humiliated his ex-wife by cheating.He insulted his children by demonstrating that he didn't think their mother deserved the respect of monogamy until a separation. He showed himself to lack the discipline to focus on the marriage and the children until a separation. He's the one who has some apologizing to do. He's lucky he's getting an invite. LW needs to stop complaining and be happy that the kids might reconcile with him. Or she might get to be the next ex-wife.