I know how hard it is! Even though I felt many times, I wish I hadn't said anything to others, I had to tell myself, (as I have learned here), "what others think about me or my AH is none of my business!" Figure out what works for you (how much to tell or what to tell or to not say anything at all.)
As a codie myself, I always feel badly by not giving a "nice" answer, but I admire people when you ask them something they don't want to answer and they tell you upfront, "I don't discuss that!" It feels "rude" but I am working on saying what works for me. I try to say, "My husband and I are separated." Most people don't ask further. When they do, I am trying to say, "I rather not discuss it." It is soooo hard, but the times I have, it actually felt good!
I am trying to find the most neutral, honest and comfortable (yet non-revealing) way to respond to questions people ask (that I don't really want to answer).
Good luck!