My lesbian partner "Diane" has been out forever. Her big sister "Millie" has always been, well, an evil, judgmental hag! When Diane told her sister she was gay, Millie at first wouldn't speak to her, then warned her never to tell their parents because they would reject her utterly. Turns out that mom and dad are fantastic and very supportive. Millie completely ignored our Civil Partnership and has told Diane she's going to hell, etc., on many, many occasions.

Then Millie had a revelation—she's into kink! Millie quickly graduated from chatting online to meeting people IRL. Her husband thinks it's just to chat, but she’s playing. She's convinced that because there’s no P-in-V that this isn't really cheating and Millie is very happy about her new, secret life. And Millie has only told Diane about this stuff because ALL Millie's old friends are in the same judgmental, gay-hating church that Millie STILL belongs to and if she told them they’d be horrified!

Millie hasn't even close to acknowledging—let alone apologizing for—all all the horrible things she's said and done to my partner over the last twenty years. I’m furious! I want to tell Millie what a massive hypocrite she's being! But my partner just wants to forget she was ever told anything about any of this. (It's not an anti-kink thing—Diane just really needs a brainbleach, because she did not need those images!) Millie is lying to everyone! She's lying to her husband and kids and family about what she’s up to! And she's lying to all her new kinky friends, who she’s presenting herself to as an open, friendly, sex-positive kinky person. I have no idea how she justifies cheating with multiple strangers but sees our 18-year relationship as an offense in god’s eyes!

Plus horrible people don’t deserve all that fun! What should I do?

Furious About Maliciously Idiotic Lying Yahoo

My response after the jump...

Here's what I think you should do: nothing.

When it comes to your spouse's family-of-origin (FOO), FAMILY, it's generally a good idea to defer to your spouse. Unless your spouse's preferred course of action—or inaction, as in this case—puts you, your spouse, or your kids (if and/or when you have any) in some sort of danger, allow your spouse to manage your relationship, as a couple, with her own FOO. You can make your feelings known, of course, and you can certainly tell the wife what you believe she ought to do. But once you've had your say... then STFU and let her handle her own FOO.

Yes, Millie is a bigoted, lying, hypocritical CPOS—"cheating piece of shit"—and that BLHCPOS owes you both an apology. And you might be able to extract one from the BLHCPOS, FAMILY, if you rub Millie's nose in her own crap long enough. But would the BLHCPOS's apology be sincere? That seems unlikely. Someone who lies to her husband, kids, and her kinky new friends is more than capable—I hope you're sitting down for this—of issuing an insincere apology to her sister's wife.

And let's be honest, shall we? It's not really an apology you want. You want revenge. You wanna see Millie exposed for the BLHCPOS that she is. And you can rest assured, FAMILY, that one day you will. Sooner or later your partner's sister is going to get caught—these aren't the sorts of secrets that keep—and seeing Millie exposed as a BLHCPOS before your wife's entire FOO then will be much sweeter revenge than hearing a lying apology now.

That said, FAMILY, please don't do anything to expose the BLHCPOS yourself. You don't want to give Millie the opportunity to cast you as the villain in the piece.