elephant-in-the-room

There'a a phrase, "the elephant in the living room", which purports to describe what it's like to live with a drug addict, an alcoholic, an abuser. People outside such relationships will sometimes ask, "How could you let such a business go on for so many years? Didn't you see the elephant in the living room?" And it's so hard for anyone living in a more normal situation to understand the answer that comes closest to the truth; "I'm sorry, but it was there when I moved in. I didn't know it was an elephant; I thought it was part of the furniture." There comes an aha-moment for some folks - the lucky ones - when they suddenly recognize the difference.