To give a bit of background, I'm friends with an ex-work colleague and both of us remain in contact with several people who still work at our old workplace and occasionally go to social functions with them. Me and my friend no longer work there, just to clarify as this is a potentially important point to consider.
A guy who still works there (who I'm closer to than my friend is) told me a week ago other ex-colleagues have found my friend's secret Twitter account which has quite risqué content on it. I don't want to go into specifics in case this identifies any of us involved but it contains very sexualised posts that, because it's under a pseudonym but with her real photo, I imagine she would be mortified to discover anyone who knows her through work, past or present, has uncovered this. This guy said people have been mocking her over it and getting as much mileage out of this as possible basically.
My loyalties lie with my friend, my only reservations about telling her is she has had a stressful 12-18 months and is now in a better place so I don't want to cause her additional stress but at the same time, what if someone else tells her in a malicious way what has been found and it would be better coming from me breaking it to her in a sensitive manner, supporting rather than shaming her over this? I want to be a good, honest friend and pride myself on being this but I don't want to cause her embarrassment or stress.