Mind my own or tell her to be careful?

[Lovecat]

Okay, 3 people involved besides myself, let's call them A, B & C - we all work together. None of them MN, so hopefully I'm safeish in asking this question.

Me & A, known each other for ages, lots of friends in common. He can be a stirrer and has been quite malicious in his gossip in the past so I tend not to tell him anything personal, as I find it being repeated back to me by another member of our circle but at a very skewed angle, iyswim.

Got to know B through A, we are now good friends and socialise independently.

C is a friend on a social level to B and me, but thick as thieves with A.

If you've managed to follow this so far, well done...

Anyway. B's marriage (to another co-worker) is in trouble. She was msning when drunk, wrote a big message to C, detailing a lot of personal stuff that she has already told me in private, bit of a 'pour your heart out' thing and certainly nothing that I'd ever repeat.

Saw A today at lunch, he said something about B's marriage, I was non-committal, he then told me that C had forwarded him the details of B's msn (!) and he knew everything.

A absolutely hates B's husband (career-related thing, not because of anything he's done to B) and would (based on past performance) use any 'damaging' info against him at any opportunity.

I'm really disgusted with C's behaviour and feel like I should warn B not to tell her anything that she doesn't want A to know about... but B is the sort of person to go and have it out with C, then it would become obvious to A (and C) that it was me who told her... not that I particularly want these people as friends, tbh, but it would make the working environment very difficult.

So WWYD? Tell or keep quiet?

[BitOfFun]

Stay out of it.