BBC News New York correspondent Nick Bryant
Co-dependency is commonly defined as "an emotional and behavioural condition that affects an individual's ability to have a healthy, mutually satisfying relationship".
Another term for it is "relationship addiction". People form and persist with relationships "that are one-sided, emotionally destructive and/or abusive".
Sitting in the atrium of Trump Tower on Tuesday, as Donald Trump harangued the press - well, you know where I'm going. For all the abuse, for all the belittlement, we as reporters show no sign of ending our relationship addiction with Donald Trump.
Much of our cravenness is easily explained. It stems from the record-breaking television ratings that Trump has generated and, just as important these days, millions of online hits.
A human headline, he more than satisfies the viral requirements of our new media age. At a time when media organisations are struggling still to monetise online news content, and to make the painful shift from print to digital, along comes the ultimate clickbait candidate, a layer of golden eggs.