From my personal observations, it seems very hard for the human brain to live with lies which are not technically lies, and at the same time remain un-damaged in other ways. I have this concept marked as one of the major leading causes of "pretzel-brain".

The most interesting example I have found so far is of an individual who thinks of himself as always honest - and he maintains this image by never lying at the meta-level. He introduces himself as a liar to all new people he meets, and, if asked directly if a statement he's made is a lie, he will answer truthfully, to the best of his ability. It's not technically a lie if people know you're honest, and can catch you in the act if they try.