Seeking Answers--if that last wasn't a rhetorical question, the answer is that their sense of entitlement is in direct proportion to the damage done in their childhoods, when their basic emotional needs were not met. Of course, the MLCers are misdirecting the anger which they couldn't express as children. They are acting out and reasoning like children, which is why they are so self-centred.
Looking at them, we think, "But they were able to keep it together and behave like adults for the last 20 years--why are they choosing to do this now?" But it's really not a choice, it's a compulsion to finally deal with the hurt they were dealt as children. Once they are in the grip of depression, they can't shake it off unless they can make it to the other side of their MLC.