I have the same issue. I'll be in pain about something and end up oversharing with someone who might go repeat it to the wrong person. Then I'll be petrified for weeks, waiting for the whole thing to explode in my face. Especially in my professional life, oh man have I overshared and regretted it. Perhaps you should try to build a small group of close friends--could be online people or whatever--that you vent to, so that you're less likely to gush to the wrong person. Also, when we mix with people we knew from long ago, it's easy to revert to that person you used to be. Maybe that's partially what happened when you started talking with your old friend and you just felt lulled into your old closeness.


For the sake of your peace of mind, could you just re-reach out to her and apologize for going on about those things, and then ask her to please not pass it on? Maybe briefly explain that you don't really have anyone to talk to and you're going through a really rough time? I've done that a few times, where I realized I overshared and I just called the person up to apologize and request they be discreet.