When it comes to lying, there are actually many ways and many conditions that can also make us lie, or cause something to constitute as a lie. In essence, it is basically an action or a speech that is created and designed to deceive others. We can be telling the truth at the wrong time to distract people from the real issue, and that can be lying as well. Deception can come in many, many different forms and going round the bush and bringing up the past is just a cover because it is either that person is trying to deceive you that those are the real reason for the problem, or that they are deceiving themselves that it is the problem and to them, they are just explaining to you the reasons. If its the former, it would be easier to remedy as compared to the latter. Self deception is the hardest and ultimate form of lying as we create the negative karma of lying day and night and to every single person we meet or talk to.
Self deception is often done when someone is unable to face a certain situation and they need a padding or cover for their weaknesses. As a result, they are no longer able to tell the truth and the false, and it develops into habits and it creates a huge dent in the way their mind operates. This is why some people who have been through traumatic experiences tend to have a mind that is a bit...broken as they try very hard to deny what is happening but the more they do, the more they damage themselves as they know it is not the truth. The western psychologists have a very fancy word for this set of disorders, they call it borderline personality disorder which is basically a dysfunctional mind that has a psychological flaw that prevents ordinary human interactions.
I have a friend that lies constantly and is extremely inconsistent with what he says and what he does. He would say one thing, a few days later he would say something different that entirely contradicts what he said a few days earlier. He tells me he is lonely and has no friends but as time passes by he tells me of his other friends. It was very very frustrating and it was scary to be with someone who is unable to just get straight to the point. I confronted him for lying and he threw a hissy fit and insisted that he was telling the truth and that i was delusional when there were so much inconsistencies with his statements. It was horrible to have a friend like this as there was no way to know what can be trusted and what not. When he lies, he sounds like he really and honestly believes in it because he is lying to himself.
I described his condition to a psychologist friend of mine, and he said it sounded like borderline personality disorder...seems like he's been living in this mode of self denial for so long that his mind is no longer able to operate without lying to himself and only listening to pleasant words and throwing a fit when exposed or hearing something difficult. That to me, is the ultimate form of lying.